What is lung cancer? An overview
The uncontrolled and undesired growth of abnormal cells in the human body is known as cancer. It is the second major cause of mortality globally, but the survival rate is increasing due to diagnosis at an early stage and cancer therapy. Cancer may occur in any part of the body, which comprises millions of cells. Cancer develops when the older cells neither die nor damage, and new cells are continually produced. In some cases, cancer may form a mass of tissues known as a tumor, while in other circumstances, as in blood cancer, there is no solid tumor.
In this article, we’ll go through the causes, symptoms, diagnostic, and treatment methods. After reading this article, we will highlight the leading causes of lung cancer, including but not limited to smoking. If you have symptoms, you’ll be able to spot them early in the course of the disease. This will facilitate the process of diagnosis. Some people are unaware of cancer medication and treatment process, but understanding them is essential to choose the best-suited method of treatment according to the type and stage of cancer.
In the article, we will also cover topics such as passive smoking as an alarming but often silent cause of cancer. So, after having a bird’s eye view, you will be able to protect yourself from this fearful condition.
What is lung cancer?
It is cancer that develops in the lungs. Lung cancer is also known as bronchogenic cancer or bronchogenic carcinoma. It is life-threatening cancer because it can invade surrounding body parts such as adrenal glands, liver, brain, and bones. Smoking and tobacco are the most significant risk factors for lung cancer.
At an early stage, lung cancer symptoms are not apparent because signs occur when the disease advanced. Signs of lung cancer include chest pain, wheezing, bone pain, weakness, headache, weight loss, shortness of breath, coughing, and hoarseness. Lung cancer can affect facial nerves leading to small pupils and drooping of the eyelids.
Sometimes, lung cancer may also produce hormone-like substances that cause additional symptoms such as nausea, confusion, coma, high blood pressure, and vomiting. Other risk factors increase the chance of developing lung cancer, such as smoking, exposure to radon (a naturally-occurring radioactive gas), exposure to tobacco smoke and radiation, family history, and exposure to carcinogens.
Lung cancer cases in the United States
The ratio of lung cancer is higher in men than in women. Lung cancer is diagnosed approximately in 121,680 men each year in the US. In contrast, about 112,350 women are diagnosed each year in the US. In 2018, 154,050 people of America died due to lung cancer. The American Cancer Society predicted approximately 235,760 new lung cancer cases and 131,880 deaths from lung cancer in 2021.
Lung cancer is widely categorized into two kinds. “Non-Small Cell Lung Cancer (NSCLC)” is the most commonly diagnosed. This type of cancer usually develops in the outer part of the lungs or the respiratory tract. It neither invades nearby tissues nor requires immediate treatment. The second type of lung cancer is Small-Cell Lung Cancer (SCLC). The overall percentage of occurrence is 15-20%. It grows faster than NSCLC and invades surrounding tissues.
The tumor may be malignant or benign. If cell growth breaks the barrier of cell tissue, invade and spread into nearby tissues, it is known as a malignant tumor. Unlike malignant tumors, benign tumors don’t invade and spread into nearby tissues. Some general cancer symptoms include fatigue, persistent coughing, weight changes, jaundice, headache, and bone fractures.
However, there is no single cause of cancer. Genetic factors and environmental factors both have the potential to cause the disease. Common triggers include heavy alcohol consumption, smoking, poor nutrition, radiation exposure, physical inactivity, infections, and excessive body weight.
The outcome of treatment improves when lung cancer is diagnosed at an early stage. It can be diagnosed by specific tests.
- The first method is through imaging tests. In the imaging evaluations, the X-rays show the mass of abnormal cells in our lungs or a nodule. After this, a CT scan is performed to reveal the extent and type of cancer.
- The second method is sputum cytology. If someone is having deep coughing and producing sputum, this test is performed. The sputum is observed under a microscope to look for lung cancer cells or another infection.
- The third method is through tissue sampling. In this case, the doctor performs a biopsy by using an instrument that passes through our throat to the lungs and pinpoints the infected area. The biopsy can be achieved with a closed or open method.
Different types of treatments can be recommended, but none of them is tagged as the perfect solution for all kinds of cancers. The treatment depends on the extent and type of cancer. The most frequently used methods are as follows:
Surgery features the complete removal of the tumor. Three kinds of surgery methods are practiced in the treatment of lung cancer.
Lobectomy: In lobectomy, the affected lobe of the lung is removed.
Pneumonectomy: In pneumonectomy, the entire lung is removed. It is practiced when the cancer is in the center of the lung.
Wedge resection: In wedge resection, the limited part of the lung is removed. Before surgery, an electrocardiogram and spirometry are carried out to check the health state of the patient.
In radiotherapy, different radiations are applied to destroy cancerous cells. It is practiced if the patient is not healthy for surgery or can control cancer symptoms, especially pain. The radiations can be directed on the affected part or can be passed with a catheter.
In chemotherapy, different medicines are taken by patients to cure cancer or to shrink it before surgery. This treatment takes place in a cycle, in which drugs are taken for some days, followed by a break period for some days. The number and duration of the cycles depend on the type and extent of cancer spreading.
In immunotherapy, medicines are taken to boost up immunity. So, immunotherapy fights against cancer and kills cancerous cells with your own immune cells and substances. It is mostly used along with chemotherapy. These medicines are usually given intravenously but can cause fatigue, joint pain, and swelling, etc.
The use of chemotherapy and radiation in cancer treatment can cause some adverse effects such as hair loss, skin-damaging, mouth sores, and vomiting. Supportive therapy can be adopted to suppress these adverse side effects.
Some home remedies can also be practiced to find some relief. These remedies include massage to alleviate pain and anxiety, acupuncture to ease the pain, nausea, and vomiting, over-the-counter and herbal medications to reduce stress, hypnosis to help with anxiety, and yoga to improve the sleeping pattern.
Breathing is so fundamental to stay alive that many cultures associate the act of gas exchange to actually having a living soul. The lungs are the main organs of breathing in humans and mammals, and they play an important role in the equilibrium of our metabolism.
Without oxygen we could not live. Our cells need oxygen to convert glucose into energy molecules called ATP. With ATP, cells create new things, move around, and complete their functions faster. You could say that oxygen is fundamental to recharge the batteries, and without oxygen cells would not function and end up dying. That’s why the breathing process does not depend on our command. The body is making sure that we’re not in danger just because we forgot about breathing for a while.
In this article, we’re exploring some early concepts about lung physiology. We’re telling you a bit of what happens inside the body with oxygen. Then, we’re walking you through the process of breathing, and numbering the different volumes of air we always have in our lungs.
Why are the lungs so important?
As noted in the introduction, each cell of the body needs oxygen to remain healthy and keep on living. Besides taking oxygen, our body has to get rid of carbon dioxide gas. Carbon dioxide is a waste gas in our body that originates from our cell’s daily activities and functioning. When we breathe in and out, our lungs exchange oxygen and carbon dioxide gases.
This is not only important to create ATP. Breathing is also a critical function to maintain our pH levels. pH is a measure of how many free hydrogen molecules are there in the environment. An acidic pH means that you have many hydrogens and hydrogen donor molecules. An alkaline pH means that you don’t have many hydrogens around and the substances are mainly oxygen receptors. Oxygen acts as an alkaline substance while carbon dioxide acts as an acidic substance. When you breathe, you’re also neutralizing the acid in your blood.
But remember that too much of a good thing is not always a good thing. When you breathe rapidly for a very prolonged period, say 4 or 5 hours, there’s a risk of turning your pH alkaline, which is also very bad. This typically happens to some patients who hyperventilate in the emergency room, especially those severely ill, and it is known as respiratory alkalosis.
The lungs work like a pair of bellows. They take oxygen into the body as they stretch. They remove carbon dioxide as they contract. However, the lungs don’t have muscles to pump oxygen in and out. Instead, they are pumped by the diaphragm and rib cage in the respiratory mechanism. Bellows do not activate themselves. You need to activate them using the handles and your own force. Similarly, the lungs are inert by themselves and stretch thanks to respiratory muscles all over the chest.
A word about lung physiology
The primary function of the lungs is to exchange gases. These gases are carbon dioxide and oxygen. The lungs are then responsible for oxygenating our blood through the respiratory mechanism. This respiratory process takes place in two phases, known as inhalation and exhalation.
- During inhalation, the ribs are elevated when their muscles contract. Simultaneously, the diaphragm contracts and is lowered. When the rib elevates, and the diaphragm is lowered, the area of the thoracic cavity increases. With this increase, the pressure on the lungs reduces, and they expand. The difference in pressure between the lungs and the air outside causes gas diffusion from the atmosphere into the lungs to equalize the pressure.
- After the gaseous exchange of oxygen, the carbon dioxide is expelled out in the process of expiration. During expiration, the ribs’ muscles relax and regain their original position, and so it happens with the diaphragm muscle. As a result, the diaphragm raises and recovers its dome-like structure. The thoracic cavity area is reduced, and the pressure on the lungs increases, so they contract, and the air flows to the outside.
The lungs have a peculiar way of safeguarding themselves. The bronchial tubes are lined with cilia, which appear like a layer of very tiny hairs. These cilia produce mucus to trap and move microorganisms out of the airway. The second defense mechanism of the lungs is the alveolar macrophages. These are white blood cells on the alveoli’s surface, and they kill and digest foreign particles like dust.
Pulmonary volumes and lung capacity
Similar to a bottle that you can fill with water up to a point, the lungs also have a limited capacity to hold air. The maximum capacity of air that your lungs can hold is known as total pulmonary capacity, and it is around 5,900 mL of air. Surely, this measure depends on your age, sex, and size.
This doesn’t mean that you fill your lungs with almost 6,000 mL of air every time you breathe. Actually, you use less than 10% of your lung capacity for each breath you take. Here’s a list of the most important pulmonary volumes:
- When you breathe normally and without even realizing, this exchange is called Tidal Volume. It is around 500 mL of air that goes in and out.
- But let’s say that you’re breathing normally, and extend one of those breaths until you can’t breathe any more air. This extra volume of air that is coming in is called Inspiratory Reserve Volume, and the measure is around 2500 and 3000 mL.
- You go back to breathing normally, but then decide to exhale some extra breath that you would in automatic breathing. There’s also a limit, and this extra volume that you’re exhaling is known as Expiratory Reserve Volume. It measures around 1,200 mL.
- But even after exhaling all the air you can, it is impossible to leave your lungs without air. There is always a small volume left, known as residual volume or reserve volume. It is around 1,100 mL of air that you won’t be able to take out of your lungs in forced expiration.
You might wonder why are all of these facts important for you. If you’re breathing normally, you won’t probably bother much about volumes, capacity, lung lobes, or respiratory function. But each one of these physiologic measures are important to diagnose a pulmonary condition. They are often affected in patients with diseases such as lung cancer, chronic obstructive pulmonary disease, pneumonia, asthma, or pulmonary fibrosis. That is why it is so important for doctors to know about physiology, and for patients to understand a doctor’s jargon and what is happening inside of their bodies.
Hall, J. E., & Hall, M. E. (2020). Guyton and Hall textbook of medical physiology e-Book. Elsevier Health Sciences.
Cotes, J. E., Chinn, D. J., & Miller, M. R. (2009). Lung function: physiology, measurement and application in medicine. John Wiley & Sons.
The core of the respiratory process is a pair of organs we can call the lungs. The lungs are made up of spongy tissue and located inside the rib cage and over the diaphragm. They constitute the main organs in the respiratory system and play a significant role in body waste management.
In this article, we’re briefly walking you through what you need to know about lung anatomy and physiology. After you’re done reading, you will understand how your lungs work. You will also become able to point to a section of the lungs and feel more comfortable when listening to your doctor talk about parts of the respiratory system.
Important data about the lungs
Like other organs in our anatomy, the lungs are found in pairs, but their size is not equal. The right-side lung is wide but shorter in length due to the liver’s presence on that side, right beneath but separated by the diaphragm. The left-sided lung is narrow due to the presence of the heart on that side. Despite the differences, our lungs can work in unison with stable and uniform movements that do not override each other.
The capacity to hold air is much higher for men than women. The lungs are air-filled organs of a pinkish-grey color. They are elastic, which is fundamental to stretch appropriately. The right lung’s weight is 600 grams, and the weight of the left lung is 550 grams approximately.
They are both the respiratory system’s main organs, and you can see them in anatomy drawings divided into different lobes or zones by oblique and horizontal fissures. The right-sided lung comprises three lobes known as the upper, middle, and lower lobes. In contrast, there are two lobes in the left-sided lung, known as upper and lower. Oblique fissures divide these lobes, and each one gets a different branch of the respiratory tube.
The lobes are composed of sponge-like tissue, and the lungs are then enclosed by a pleura membrane, which isolates them from the chest wall. The pleura is a double-layered membrane that covers the lungs, and between them there’s a liquid called pleural fluid.
- The visceral pleura is the inner layer of the membrane. It is very tightly bound around the lung, and the primary function is to prevent it from peeling off.
- The outer layer of the lung is also known as the parietal pleura. The role of the outer layer is to cover the inside of the thorax.
- The pleural fluid prevents friction between these two layers. It provides lubricant function for contraction and expansion of the lungs during respiration.
Both lungs have their pleural sacs. Thus, when a lung is deformed, the other stretches further and continues functioning.
Anatomically, each lung adopts sort of a triangular shape, consisting of three borders and three surfaces with a base and apex.
- The surfaces of the lungs are known as mediastinal, diaphragmatic, and coastal surfaces. They form the three borders of the lungs.
- The borders of the lungs are known as interior, inferior, and posterior.
- The Interior border is the sharp border that forms by the fusion of “mediastinal and costal surface.”
- The inferior border is formed by separating the lung’s base from the “mediastinal and costal surface.”
- The posterior border is the rounded border that forms when the “costal and mediastinal surfaces” meet from the backside.
The Respiratory system
The lungs begin from the trachea’s underside, which is one of the most critical parts of the respiratory tube. It is a pipe-like structure, also known as the windpipe. The trachea length is about 10-11cm, and the width is 1.5-2cm. It comprises 16-20 cartilage rings, each one adopting a C-shape to prevent the trachea from collapsing.
After connecting with the pharynx, the trachea enters into the chest cavity and splits into two tubes of smaller sizes known as bronchi.
- The right bronchus has more length and width than the left bronchi. The length of the right bronchi is 2.5cm.
- The left bronchus is smaller in size than the right-side bronchi. Its length is about 5cm.
You can also find cartilage in the bronchi, but the shape resembles plates instead of a C letter. These two tubes enter into their respective lungs and divide into smaller branches. Even after entering into the lungs, they continue to divide and form fine tubes called bronchioles.
In the bronchioles, there is no cartilage. They further divide and form alveolar ducts, which end in a structure similar to a bunch of grapes. This is a cluster of alveoli. The alveoli are sac-like structures made up of epithelial cells.
A network of capillaries covers the whole structure. These alveoli and capillaries play a leading role in the respiration process, which is powered by a muscular structure called a diaphragm located under the lungs. The shape of the diaphragm is similar to a dome. It is a major muscle in the respiratory process to exhale carbon dioxide and inhale oxygen gas. Other muscles also contribute to the process as accessory breathing muscles.
What happens is that the lungs stretch during respiration, not because the muscles are somewhat attached to the lungs. They stretch because they are in an enclosed space with negative pressure. When the breathing muscles move, they increase the available space and the lungs stretch passively. So, breathing consists of a constant change of pressure instead of active lung movement.
As you can see, the lungs are spongy structures that do not breathe by themselves. They need external muscles to perform their breathing function. They have different lobes and a complex set of respiratory tubes and their branches. Such different tissues and cells work together towards one vital function, which is breathing. It is the exchange of oxygen and carbon dioxide that maintains our cells healthy and ourselves alive.
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Lung Cancer Symptoms
The lungs are one of the most critical organs that keep us alive along with the heart. If one of those stops functioning, that means instant death. As such, a tumor in one of these organs and obstructing their functions is often dangerous, especially if we’re talking about cancer.
Lung cancer is divided into small cell lung cancer and non-small cell lung cancer. This latter category includes different subtypes. But they all have similar symptoms, each one described by patients differently.
In this article, we’re exploring the most important signs and symptoms of lung cancer.
Cough is one of the main symptoms of lung cancer as the lungs’ oxygenation function is obstructed by the tumor. As it grows further, the cough becomes worse and starts becoming a daily problem, sometimes bringing out blood as well. In these cases, coughing is meant to clear the airways from any debris or obstruction. What the body is doing is perceiving cancer and trying to clear it out. Thus, cough symptoms are much more common if cancer is located in the central parts of the lungs, where the airways are located.
Cough is also a common symptom in other respiratory diseases, and most of them are benign. However, you need to pay special attention to cough when it lasts for more than 8 weeks. This is a chronic cough, and it is not usual in respiratory infections or the flu.
Frequent respiratory infections
Patients with lung cancer may become more susceptible to respiratory infections than the average population. They are not only viral infections and flu-like symptoms. We’re talking about more aggressive types such as bronchitis and pneumonia. They are more common still if the patient is undergoing cancer treatment with radiotherapy and chemotherapy.
In these cases, the characteristics of your cough are vital to understanding the source of the problem. You might need to get a sample of your sputum to see what’s in there and the type of bacteria that is affecting you. In the sputum, doctors may also find cancerous cells, primarily if the tumor is located near the airways. In any case, the recurrence of respiratory infections is always something to evaluate, especially in patients with a history of tobacco smoking and chronic cough.
This is the symptom of coughing up blood, which is only mentioned in the cough section of this article. In many cases, lung cancer is only perceived when the patient starts coughing up blood. However, by this time, the tumor is usually big enough to compromise the lungs’ blood vessels. Other conditions, especially tuberculosis, also trigger hemoptysis, and it is usually not an emergency. However, it is a significant symptom of a chronic disease that should not be neglected.
What happens in cancer is that the tumor creates new blood vessels and dilates the existing arteries to obtain more blood flow. But the new blood vessels are fragile and prone to bleeding. They are abnormal blood vessels that tend to break when the patient is coughing. This symptom requires close evaluation, and it usually requires X-rays and other imaging tests to evaluate its cause.
This symptom is very important to diagnose lung cancer, and it is usually felt as pressing or throbbing pain in the thoracic area. The pain worsens as the patient coughs or sneezes, but it still lingers even if the patient is not coughing, usually reported as discomfort. Chest pain can indicate the part of the lungs affected by lung cancer, but it is sometimes not specific. As the disease progresses, the pain remains and becomes worse. Even mild pain becomes irritating and problematic in these patients because of the chronicity of symptoms.
What is happening is that cancer tumors create inflammation in the nearby tissue, and by itself, it presses upon other structures. Inflammatory substances make contact with nerve terminals and activate the sensation of pain. As the tumor presses upon other structures, they also affect the nerve terminals mechanically, triggering the sensation of pain.
Shortness of breath
Not being able to breathe or having difficulties taking a deep breath is a common problem in patients with a tumor in the lungs, especially in cancer. These tumors can be located in different parts of the lungs, and when they are near the airways or directly obstructing them, the sensation of shortness of breath is more intense and annoying. This symptom’s clinical name is dyspnea, and it is often accompanied by pain as the patient breathes deeply.
Different lung conditions can trigger shortness of breath, including infections, because they trigger inflammation and swelling. Something similar happens with lung cancer, but in addition to that, the tumor creates a physical obstruction, and sometimes a condition known as atelectasis appears, in which the air sacks collapse instead of being full of air. This reduces the air capacity of the lungs and affects the patient’s breathing function.
Fatigue and weight loss
Patients with lung cancer undergo a syndrome known as cachexia when they reach an advanced disease stage. In cachexia, we have three main symptoms: chronic fatigue, loss of appetite, and unintended weight loss.
These patients have a very high metabolic rate because cancer takes up many resources from the body. As a part of the disease and the inflammatory condition, they tend to lose their appetite. And even if they do not reduce their intake, weight loss is very likely because the tumor is robbing the blood’s nutrients at a very rapid pace.
All of these signs and symptoms are found in lung cancer, but most of them can be found in other benign diseases as well. Thus, if you have one or more symptoms listed above, it does not automatically mean that you have lung cancer. Talk to your doctor, and you will go through a series of exams to see what is going on and what is the most appropriate solution for you.
Pneumonia is a lung infection in which there is an accumulation of fluid in the lungs, and the patient suffers from breathing difficulties. The tumor growth in the lung tissues increases the chances of developing pneumonia and weakens the patient’s immune system suffering from lung cancer. There is an accumulation of fluid in the cavity between the walls of the lungs and the chest, which leads to the breathing difficulties in the patients. The doctors suggest that there is frequent pneumonia in the patients with lung cancer as the state of the lungs is at stake due to the overgrowth of the cells in the tissues of the lungs.
Bronchitis is an infection of the airways in the lungs. In lung cancer patients, there is irritation and inflammation of the bronchi, which worsens with the tumor growth. In combination with the two other lung infections, bronchitis, pneumonia, and emphysema are in later stages of lung cancer. While some patients only develop chronic bronchitis, the doctors suggest that these patients do not progress towards the later stages of lung cancer. Some patients also develop asthma and tuberculosis, and bronchitis, thus indicating tumor growth in the lungs. There is an increase in mucus production in the airways, leading to the blockage of airflow through these air passageways in the patients with bronchitis. The persistent symptom of bronchitis leads to the lung damage, which is mostly permanent and greatly reduces the lung function.
Loss of appetite
Lung cancer patients usually suffer from loss of appetite due to the changes in taste, nausea, or chronic pain. The patients with lung cancer start eating less than the average amounts of food and lead to the eating disorder of anorexia, which ultimately causes weight loss. The blocking of the airways and the fluid accumulation in the chest cavity makes the lung cancer patients to eat less or not eat at all. The loss of appetite in lung cancer patients is medically known as cancer cachexia, which leads to muscle wasting and unintentional muscle wasting.
Fatigue and weakness
There is a sensation of weakness and lack of energy because cancer lowers the number of red blood cells in your blood and, consequently, lesser oxygen to provide power. The patients with lung cancer experience persistent weakness and fatigue, and no matter how much the person rests or sleeps, there is no relieving from fatigue. The destruction of red blood cells and the lack of energy available for the body to make enough red blood cells make the person feel tired and weak all the time. The systemic weakness symptom is prevalent and becomes intense with the progression of cancer.
The tumors in the lungs block the airways and cause several breathing infections. There is a repetition of respiratory infections in patients with lung cancer, and these infections are recurring. The infections in the respiratory system might arise due to the blocking of airways. The tumor grows persistently, making it difficult for the lung to expand during the inhalation process fully. The primary respiratory infections resulting from lung cancer include lower respiratory tract infection (LRT) and bronchitis.
As we know, lung cancer symptoms also appear depending upon the tumor growth location on the lung. The metastasis of tumor occurring in the lung can reach to other body organs and might result in symptoms such as:
Lung cancer leads to the developing pain in the ribs, back, or hips as cancer in the lungs spread extensively to the bones. According to the studies, almost 30 to 40 percent of patients with lung cancer develop bone metastasis during the disease’s progression. The lung cancer spreads into the bones and causes bone Mets, and these tumor growths are relocating from the primary tumor in the lungs.
Spinal cord and brain
The metastasis of tumors in the spine results in dizziness, headache, balance problems, or numbness. The tumors in the spine driving from the primary tumor in the lung progresses rapidly, and unfortunately, there is a poor prognosis for the treatment of this type of cancer. The spine tumors rapidly result in the patient’s paralysis in most cases, and the treatment is challenging for metastatic spine tumors.
The primary tumor of the lungs causes the development of lumps in the neck or the collar bone as cancer spreads to the lymph nodes in the nearby area in the extensive stage of lung cancer, when both of the lungs are suffering from tumor growth then the lymph nodes on both sides of the lungs suffer from cancer. There is swallowing of lymph nodes and glands in the chest area and leads to the stomach’s swallowing if cancer reaches the liver.
In non-small cell lung cancer (NSCLC), there is a spread of lung cancer to the body’s distant organs, including the liver. There is yellowness of skin and eyes or jaundice, which indicates the liver metastasis, and the cancer cells develop aggressive tendencies. The cancer cells float in the blood circulation and start replicating themselves in new areas. The prognosis of liver metastasis due to lung cancer is almost five years, giving a survival rate of 5 percent.
The tumors forming at the upper portion of the lungs might result in the development of Horner syndrome, which causes symptoms such as:
There is severe pain in the shoulder, hand, arm, and scapula due to lung tumors, which affects the bones of the body, as mentioned earlier. There is a release of calcium ions in the bloodstream from the bones, leading to higher calcium levels in the blood, which further causes pain in the body.
Lack of sweat on the face
The tumor growing in the lungs causes the disruption of nerve stimulations of the central nervous system towards the face. There is a lack of sweating on the face’s area affecting the disruption of the nerve pathway.
Reduction in pupil size
There is constriction of the pupil, which is medically known as meiosis due to the nerve pathway’s disruption. The cancerous cells from the tumor in the lungs resulting in the disruption of nerve signals towards the face, and the reduction in pupil size happens on one side of the eye in most cases. The two muscles that control the pupil size are the circumferential sphincter muscle cells, and they are present in the iris, and the cancer cells disrupt the activity of these sphincter muscles.
Drooping of Eyelids
The disruption in the nerve signal pathway, resulting from cancer cells of lungs, causes ptosis, i.e., the drooping of the eyelids. The superior tarsal muscles responsible for keeping eyelids in raised position effects from the partial opening and the eyelids start drooping down. The eyelid drooping doesn’t affect the vision or the health of the eye but is not life-threatening.
The tumors might secrete a hormone which leads to the development of the paraneoplastic syndrome, and the symptoms include:
The patient suffering from a paraneoplastic syndrome manifests nausea as there is obstruction of gastrointestinal tracts due to the increased tumor growth. The chest cavity suffers from the abnormal growth of cancerous cells, leading to the pseudo-obstruction of the gastrointestinal tract, making the food go back towards the mouth.
High blood pressure
There is a production of systemic high blood pressure or hypertension, mainly due to the cancerous cells spreading in the lungs. There are renal malignancies in the patients with lung cancer, which significantly reduces kidneys’ function, thus leading to high blood pressure.
There is a manifestation of vomiting in the patients of lung cancer chronic obstruction of the gastrointestinal tract. The persistent vomiting leads to water retention and regurgitation of food from the stomach.
There is a loss of nerve cells, which leads to cerebral degeneration in the brain’s site where the cancer is growing after relocating from the lungs.
High blood sugars
There is acute hyperglycemia or high blood sugar, as the function of the pancreas suffers from the cancerous growth relocating from the lung tumors.
As there are degeneration nerve cells in the brain areas suffering from the attack of tumors originating from lung cancer, the patient suffers from confusion. The degeneration of nerve cells leads to confusion and loss of focus among the patients.
The paraneoplastic syndrome significantly causes weakness of proximal muscles leading to severe disability. There is an increase in serum muscle enzyme levels, which indicates the growth of cancer cells.
The PNS syndrome significantly affects the spinal cord, brain, and nerves leading to a coma condition, and it might be fatal for the patient. The comma becomes rapid and fluctuates as there is constant degeneration of nerves in the central nervous system.
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Lung cancer prognosis: Survival rate and complications
It is never pleasing to hear the word cancer in a doctor’s office, but there are many slow-growing cancers such as prostate cancer and others that only rarely migrate to other tissues, such as skin cancer. In contrast, lung cancer is in contact with the blood every minute, and a massive amount of blood goes through this organ every day, making it more likely to spread to other organs.
However, not all lung cancers are the same, and some of them are not as aggressive. In this article, we’re going through the prognosis of lung cancer. In other words, what would a patient expect from cancer in a few years. We will talk about survival rates of different lung cancer types to compare them with one another and then talk about certain complications that would increase the risk if you don’t solve the problem.
But first, it is essential to explain a critical concept: survival rate.
There are two types of survival rate: an overall survival rate and a relative survival rate, and each one refers to something different.
- Overall survival rate refers to how many patients are still alive after a given period. For example, if 2 out of 10 people died in a period of 5 years, the 5-year overall survival rate is 80%.
- The relative survival rate is the same thing, but it excludes people who died for non-related causes. In the example above, if one of those patients who died had a fatal heart attack and did not die from cancer, the 5-year relative survival rate is closer to 90%. This type of survival rate is more valuable to measure the real impact of cancer, and it is the one that we will refer to throughout the article.
In lung cancer, the 5-year survival rate is calculated taking the worldwide statistics of cancer and breaking them down into three categories:
- Localized lung cancer: In this group, you will find patients with a localized disease that has not spread inside the lungs or another organ.
- Regional lung cancer: In this group, you will find patients with localized spread of the disease. Lymph nodes can be taken, and the tumor is growing but only in the chest.
- Distant lung cancer: In this group, you will find patients with distant metastasis of lung cancer, which includes organs such as the bones, liver, or brain. It also includes cancer that spreads from one lung to the other.
With that in mind, let’s evaluate the prognosis of small cell and non-small cell lung cancer.
Prognosis of small-cell lung cancer
Small cell lung cancer is one of the most aggressive types, and most cases are detected when the disease is very advanced. There is no cure for extensive-stage small-cell lung cancer, and the survival in 7 months is 20%, while the survival in 5 years is 2%.
In contrast, if you have a limited-stage disease of small-cell lung cancer, it is likely to stay alive after 17 months for 80% of patients, and the survival in 5 years is close to 15%.
The statistics are different depending on what data we use, and according to data gathered in the United States between 2010 and 2016, this is the 5-year survival rate according to the categories listed above:
Total of patients with small-cell lung cancer: 7%
Localized small-cell lung cancer: 27%
Regional small-cell lung cancer: 16%
Distant small-cell lung cancer: 3%
Prognosis of non-small cell lung cancer
In non-small cell lung cancer, the prognosis is different for many reasons. First off, it is more common to have patients with an early disease because this type is usually not as aggressive as small-cell lung cancer. Secondly, this is a broad category and includes several subtypes of cancer, each one with heterogeneous statistics.
The prognosis depends on many things, including the stage at the moment of diagnosis, the lungs’ performance score, and whether or not the patient is losing weight. According to recent studies, the number of lymph nodes affected by cancer helps measure the survival rate.
In this group, and according to statistics in the United States from 2010 to 2016, the 5-year survival rate of lung cancer looks like this when broken down into categories:
- Total of patients with small-cell lung cancer: 25%
- Localized non-small-cell lung cancer: 63%
- Regional non-small-cell lung cancer: 35%
- Distant non-small-cell lung cancer: 7%
As noted, in almost every item, the chance of survival of non-small cell lung cancer after 5 years of the initial diagnosis doubles that of small cell lung cancer.
Complications of lung cancer
Complications of lung cancer increase the risk of dying from this disease, and it is usually related to the spread of cancer to other organs.
Metastasis and more aggressive disease are more common in small-cell lung cancer, especially when these risk factors are met:
- When the stage of the disease is advanced at the moment of presentation
- When the function of the lungs is visibly affected by the disease
- If the patient is losing weight substantially without changing their diet or exercise habits
- In patients with an elevation of lactate dehydrogenase
- In patients with an elevation of calcium or alkaline phosphatase
- In patients with low levels of sodium in the blood and other electrolytic disturbances
- In male patients as compared to females
Depending on the metastasis site, patients can develop a pleural effusion when liquid starts to accumulate around the lungs, deep vein thrombosis and a pulmonary embolism, a high level of calcium in the blood and heartbeat problems, or a spinal cord compression in case of bone metastasis.
Each condition affects your personal survival rate, which is why it is often difficult to say precisely what will happen to you after the diagnosis of lung cancer.
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Lung cancer diagnosis
Having symptoms such as cough and chest pain does not necessarily mean that you have lung cancer. These symptoms should not be neglected, but the right path to take is visiting your doctor and going through exams to figure out what is going on. Lung cancer is a possibility, but it is often the least likely.
To diagnose your problem and detect lung cancer, doctors can take different ways depending on your initial symptoms. There is also screening for lung cancer that is performed in apparently healthy individuals.
In this article, we’re briefly reviewing the most important tests and procedures doctors use to diagnose lung cancer. We’re also covering the updated recommendations for screening lung cancer in high-risk individuals.
In most cases, lung cancer will be visible through different imaging tests, including an X-ray or a CT scan. Each one is used differently and at various stages of the diagnosis.
- Chest X-rays: It is a standard procedure for respiratory conditions because it pictures the lungs and the airways very clearly. It is also the first imaging test performed in patients with this type of symptoms. In chest X-rays, lung cancer shows up as a mass or a conglomerate of masses. In some cases, patients have abnormalities in the chest’s medial structures, called mediastinum, or they can have an enlarged hilum (the section of the airways that connects to the lungs). Patients with somewhat advanced disease may have pleural effusion and thickening of the pleura. This initial finding is often confirmed with other imaging techniques, especially a CT scan.
- CT scan: It is the second step and provides a more accurate image of the anatomic properties of the mass. It is often combined with PET scans in high-risk patients to offer a more precise understanding of cancer and its staging. Combined with PET, a CT scan can be helpful to differentiate between cancer and inflammatory conditions of the lungs. They also contribute to direct a needle biopsy and detect local and distant metastasis.
Sputum and pleural fluid cytology
In patients with chronic cough and sputum, a sample can be taken to the laboratory to evaluate what is happening and what type of tissue can be found. Sputum cytology contributes to the diagnosis because some patients with lung cancer cough up particles of the primary tumor or cancer cells that will be visible under the microscope.
Another possibility is taking a sample of the pleural fluid if there is pleural effusion. Malignant cells can be found in this liquid, too. In these cases, pleural effusion is by itself a sign of poor prognosis and is usually associated with advanced lung cancer.
Sputum cytology is not always reliable, and there are many false-negative results. Thus, it is a good idea to obtain a large sample of pleural fluid or sputum to increase the likelihood of detecting cancer cells. The sample also needs to be processed immediately because if the patient takes too much time in taking the sample to the laboratory, cells tend to break down and yield a false-negative result.
Diagnostic procedures are more invasive than cytology and often require specialized equipment. However, they provide the most accurate description of cancer and the most reliable diagnosis. They include:
- Percutaneous biopsy: This procedure is commonly used in patients with suspected metastasis in the liver, adrenal glands, lymph nodes, or pleura. It is performed with a needle puncture guided by imaging techniques such as CT scan or ultrasound. It is the least invasive procedure on this list, and it is usually risky in patients with emphysema.
- Bronchoscopy: This is the most common diagnostic procedure to obtain a direct sample of the lung tumor. This exam is fundamental to stage lung cancer, and it is much more accurate than other diagnostic techniques. In this exam, a bronchoscope is used and goes through your mouth or nose to reach the airways and directly see what is happening there. The doctor may also take a sample of the tumor to perform a biopsy.
- Mediastinoscopy: This procedure is helpful in patients with suspicious mediastinal lymph nodes. It is an alternative to endobronchial ultrasound-guided biopsies, usually performed as a part of a bronchoscopy.
- Open lung biopsy: This type of biopsy is done as a part of a complex surgical procedure known as open thoracotomy. It is the most invasive technique and only performed if no other method is available to diagnose lung cancer.
Screening for lung cancer
An early diagnose of lung cancer provides a better chance of survival without complications. But most types of cancer only give out signs and symptoms when it is already too late. That’s why screening for lung cancer is essential for people with a high risk. This allows doctors to detect patients with early disease, treat them with surgical resection of the tumor, and reduce the therapy’s aggressiveness.
The usual screening method is an X-ray, but recent studies show that using a CT scan reduces the number of cancer death further. In any case, screening should be done in active smokers of 30 packs a year or more, former smokers who had quit smoking within 15 years, especially if they are 55 to 80 years.
Certain tumor markers are being studied to screen lung cancer using molecular analysis. Genes such as p53, EGFR, and K-ras are likely going to become future markers of the disease.
After detecting cancer, different methods can be used to stage the disease and guide our future directions. In this stage, it is crucial to ask all of your questions to the doctor and take your time to decide what to do and which treatment strategies to follow. Lung cancer is not an easy diagnosis to process, and you may need help to cope with symptoms or your own emotions. Talk openly to your doctor about it and discuss the pros and cons to make an educated decision.
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Lung cancer grading and stages
The lungs are in contact with a very high volume of blood for every minute. As such, it is one of the most susceptible organs for metastasis. Cancer in the lungs is also very likely to spread, making lung cancer a particularly dangerous disease. Some cases are detected before spreading happens, while others have very accelerated growth and are only diagnosed when it is too late to take the primary tumor out.
Just like any other cancer, lung cancer starts as a bunch of cells that divide very rapidly. A tumor begins to grow from these cells, only limited to one area. As the cells divide more, they start undergoing mutations, making cancer more aggressive. In time, the tumor is not limited to a small area of the lung. It spreads locally, and the cells start traveling to distant locations.
Each of these steps in the process is described by cancer stages or grades. For therapeutics, it is imperative to know in which stage cancer is before planning what to do about it, and in this article, we will review how doctors stage lung cancer and what tools do they use.
Stages of Small-cell lung cancer
Small cell lung cancer only has two stages:
- Limited stage: It features cancer that is only found in one lung. No cancer cells are found in the other lung, and if any lymph nodes are taken, they are located on the same side of the affected lung. Only a minority of patients with SCLC are diagnosed with a limited-stage disease because it is rapidly-growing cancer often detected in a late stage.
- Extensive stage: It features cancer usually found in one lung, but we have either a secondary tumor in the other lung or any other organ. These patients may also have malignant tumors in the lymph nodes located on the other side of the chest. In patients with pericardial or pleural effusion, an extensive stage would have malignant cells on the liquid.
Stages of Non-Small-Cell lung cancer
We have 5 stages of non-small cell lung cancer. They are as follows:
- Stage 0: This is the earliest stage of cancer we can have. In this case, we have carcinoma in situ (cancer that is small and limited to its own space). No lymph node invasion and no metastasis is present.
- Stage I: In this stage, cancer is still very small (no more than 1 cm) or minimally invasive carcinoma (IA1). Another possibility is having a very small tumor of 1-2 cm (IA2) or 2-3 cm (IA3). If the tumor is larger than 3 cm but smaller than 4 cm, it is also stage I (IB). There’s no involvement of the lymph nodes in this stage, and there is no distant metastasis.
- Stage II: In this stage, we have larger cancer tumors, with 3 cm or more and lymph nodes taken but only located inside the affected lung. Still, no distant metastasis is found in this stage.
- Stage III: In this case, we have a 3-5 cm tumor with lymph nodes taken not only in the lungs but also in the mediastinal space, where the heart is enclosed. Another possibility is larger than 5 cm; it can also be stage III when no lymph nodes are taken outside of the affected lung (IIIA). When mediastinal lymph nodes are taken in a tumor larger than 5 cm or the opposite lung, and other lymph nodes outside of the lungs are taken, we’re in front of a IIIB stage.
- Stage IV: In this stage, it doesn’t matter how large the tumor is and how many lymph nodes are taken. We’re in front of a stage IV lung cancer if there is metastasis. It is further divided into stage IVA when metastasis is found in the pleural space, the contralateral lung, or in a single organ outside of the thorax. It is stage IVB when more than one organ outside of the thorax is taken by metastasis.
Useful tests for staging lung cancer
Staging is done by analyzing the results of different imaging tests and biopsies. The most common tests to stage lung cancer include:
- PET or PET-CT scans: Doctors use a PET scan to identify malignant lymph nodes and metastases around the lungs and other organs. PET and CT scans can be combined to gain more accuracy.
- High-resolution CT scans: They are performed instead of PET-CT scans if they are not available. However, there are certain limitations in a CT scan because they sometimes won’t distinguish benign from malignant lesions.
- MRI scans: This technique is instrumental in evaluating the vascular supply of the diaphragm and tumors near the lung’s apex. These are known as Pancoast tumors, and it is usually mesothelioma. The vasculature exam helps plan surgery and obtain insight into the behavior of this type of lung cancer.
- Blood tests: Alkaline phosphatase levels are higher in bone metastasis, and we can also find high levels of calcium in these cases. Other practical tests include a complete blood count, bilirubin, albumin, AST, ALT, and electrolytes. These are only made to see if the patient will tolerate treatment or to rule out the presence of a paraneoplastic syndrome.
- Biopsy: When there’s a questionable node, a suspicious nodule, or an uncertain diagnosis, biopsies can help figure out if there’s cancer or not.
- Brain imaging: They are usually MRI scans, but CT scans can also help detect neurologic abnormalities and possible metastasis in patients with headaches and other neurologic symptoms.
Prognosis according to the stage
In small-cell lung cancer, the prognosis of the disease is poor because this is a more aggressive lung cancer tumor. The 5-year survival rate of patients in a limited stage is 20%. In the extensive stage, the 5-year survival rate is lower than 1%.
In non-small-cell lung cancer, the prognosis is more favorable. Patients in stage I have a 70% survival rate in 5 years. As the number of the stage increases, the survival rate is reduced, and it is also lower than 1% in the last stage of the disease.
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Types of lung cancer
Our body is made up of a trillion of cells, and all of them contain DNA. These cells replicate and form an identical copy when they divide. This is a continuous process in which older cells die, and new ones develop to replace them. Mutations take place when there is an error in the replication of cells. They can potentially cause cancer in any part of the body. Cancer that begins in the lung is known as lung cancer.
In the United States, 228,820 new cases of lung cancer are expected the next year. Lung cancer percentage has reduced by about 3% in men and 1.5% in women annually from 2007-2016. The risk is 15% higher for black men than white men, but the disease is 14% more threatening for white women than black women. The death rate from lung cancer was reduced by 51% in men since 1990 and 26% in women since 2002.
In this article, you’ll go through the various types of lung cancer, their stages, diagnosis, and treatment methods. This article will also highlight the common symptoms and complications of lung cancer. After reading the article, you’ll be able to identify the type of lung cancer by its symptoms and understand your doctor when he recommends a treatment method.
Lung cancer and its symptoms
Primary or secondary lung cancer may occur. Primary lung cancer occurs in the lungs and doesn’t spread to other parts. In contrast, secondary lung cancer occurs in any part of the body and spreads to the lungs through the blood or lymphatic system. Thus, the first type of lung cancer we need to discuss is metastasis or spread from other organs.
In any case, lung cancer can cause several symptoms. The main symptom is shortness of breath due to a blockage of airways or fluid accumulation around the lungs.
The second major symptom is coughing up blood. Sometimes, severe coughing with lung cancer can cause bleeding in the airways.
The third symptom is pain. Lung cancer in the inner part of the lung or outer part of the lung can cause body pain. Lastly, lung cancer can spread to other parts like the brain and bones. As a result, nausea, headache, vomiting, or wheezing can occur depending on which part of the body is affected.
Types of lung cancer
Lung cancer is broadly categorized into two kinds which have more subtypes. The broad categories are known as “Small Cell Lung Cancer (SCLC) and Non-Small Cell Lung Cancer (NSCLC).” The percentage of NSCLC is 80-85% across- world. In contrast, SCLC is less common, and near -about 10-15% of lung cancer is SCLC.
- Sub-types of Non-Small Cell Lung Cancer (NSCLC): The sub-categories of NSCLC are “large cell carcinoma, squamous carcinoma, and adenocarcinoma.” These are categorized on the base of their lung cells from where they start.
- Adenocarcinoma: Adenocarcinoma starts in the cells of the lungs that synthesize mucus and other secretions. This type of cancer is more common in women than men and mostly occurs in younger people. It can affect current smokers, old smokers, or even non-smokers. It is usually diagnosed at the early stage before spreading and is mostly found in the outer parts of the lung. It makes up about 40% of lung cancer cases.
- Squamous carcinoma: Squamous carcinoma occurs in the cells of the airways of the lungs. This kind of lung cancer commonly occurs in the center of the lung. The most affected people by this cancer are smokers, either a current smoker or former smoker. It grows and spreads more quickly than other kinds of lung cancer, making it more difficult to treat. It makes up about 10% of lung cancer cases.
- Large-cell carcinoma: In this case, cancer is not squamous carcinoma or adenocarcinoma. This is a diagnosis of exclusion when the tumor cannot be classified into specific lung cancer types. Thus, it is a heterogeneous group of undifferentiated cancers.
- Small-Cell Lung Cancer (SCLC): SCLC is not commonly diagnosed at an early stage. It grows and spreads more speedily than NSCLC. SCLC is also called an “oat-cancer” due to its oat-like appearance under a microscope. It mostly occurs in the bronchi of the lungs and spreads toward other body organs, the pleural fluid, and lymphatic nodes.There are two main subtypes of SCLC. This categorization depends on the cells in which it occurs and how the cells look when observed under a microscope. The two types are “small-cell carcinoma and combined small cell carcinoma.” These types of lung cancer are more threatening and require treatment as soon as possible.
- Small-cell carcinoma: Small-cell carcinoma is a subtype of small-cell lung cancer that occurs within the lung. It occurs in the cells of the central airways and narrows down the bronchial airway. Common symptoms of small-cell carcinoma are weight loss, cough, and weakness. It is a type of secondary lung cancer that can spread to other body organs such as the bone, brain, and liver.
- Combined small-cell lung cancer: Combined small-cell lung cancer occurs with other forms of lung cancer such as squamous cell carcinoma. Its symptoms are similar to other kinds of lung cancer.
Stages of lung cancer
There are different stages for both main branches of lung cancers according to how much cancer is spread. The chances of treatment increase when lung cancer is diagnosed at an early stage. Diagnosis can be achieved by specific tests such as imaging tests or sputum cytology.
- Stages of Non-Small Cell Lung Cancer: There are four stages for NSCLC. During the first phase, lung cancer is only found in the lung, and it is not very large. During the second phase, lung cancer is larger than 4 cm. Besides, it takes the lymph nodes but only inside of the lung. During the third phase, the tumor is larger, it can be spread locally in the chest, and lymph nodes outside of the lungs are taken. During the fourth and more threatening stage, cancer is very large, it has taken the surrounding areas, and it may have spread to other organs.
- Stages of Small-Cell Lung Cancer: We can summarize SCLC into two stages. The first stage is known as the “limited stage”. In the limited-stage, cancer can be diagnosed in the lung, nearby lymph node, or the chest. “Extensive stage” is after the limited stage of cancer. During the extensive stage, cancer has spread to the bone marrow, opposite lung, lymph nodes, pleural fluid, and surrounding tissues.
Small-cell lung cancer: Causes, symptoms, diagnosis, prognosis
There are different ways to break down lung cancer into categories or types. First of all, they divide into small-cell lung cancer and non-small cell lung cancer. In other words, small-cell lung cancer goes in one category, and the remaining category contains anything that is not small-cell lung cancer.
In this article, we’re briefly going through the essentials of this type of cancer and what you need to know about its causes, symptoms, diagnosis, treatment, and prognosis.
What is small-cell lung cancer?
Small-cell lung cancer is also known as oat cell carcinoma. It is an aggressive type of lung cancer that spreads from an early phase of the disease. Small-cell lung cancer is often associated with neoplastic syndromes and other medical problems such as Eaton-lambert syndrome, hypercalcemia, etc.
Since small-cell lung cancer is so aggressive and easy to metastasize, these patients need to be assessed from an early phase of the disease to figure out the disease stage and what we can do about it.
What causes small-cell lung cancer?
The most common cause of small-cell lung cancer is chronic tobacco smoking. Along with squamous cell carcinoma, this type of lung cancer has a solid relationship with the habit of smoking. Actually, around 98% of patients with this type of cancer have an active or past smoking habit. That’s why part of the treatment of small-cell lung cancer should include smoking cessation to prevent the formation of new cancer cells.
Another cause of small-cell lung cancer is uranium and radon exposition. Actually, uranium miners have a higher incidence of lung cancer regardless of the type. Radon is an inert gas that results from the decay of uranium. It is a radioactive substance, and it is another cause of small-cell lung cancer.
Signs and symptoms
Small cell lung cancer is more aggressive than other types, and most patients display symptoms. Only 5% of them remain without symptoms at the moment of diagnosis. The most common signs and symptoms include:
- Shortness of breath
- Bone pain
- Neurologic problems
- Tiredness and fatigue
- Weight loss
These symptoms are usually reported in a period of around 8 weeks before the disease is diagnosed. They are more severe as the tumor keeps growing, spreads inside the thorax or to other areas.
When the tumor grows in the lungs without reaching other areas, it causes symptoms such as:
- Obstruction of the airflow
- Irritation of the airways
- Cough, often with hemoptysis (coughing up blood)
- Collapse of the airways in aggressive cases
- A higher predisposition to pulmonary infections
When the tumor spreads into the thoracic cavity, it causes additional symptoms:
- Hoarseness when the laryngeal nerve is compressed
- Paralysis of the breathing muscles on one side of the thorax when the phrenic nerve is compressed
- Difficulty to swallow (dysphagia) when the esophagus is compressed
- A characteristic breathing noise known as stridor when the major airways are compressed
- Swelling of mediastinal lymph nodes as noted in imaging studies
- Pressure or obstruction to the venous flow in the superior vena cava with swelling of the face and arms
When the tumor spreads outside of the thoracic cavity and to distant organs, it causes other symptoms:
- Nausea and vomiting
- Headache, confusion, increased sensitivity to light, and blurred vision in case of metastasis to the brain
- Slurred speech, extremity weakness, or sensory abnormalities in case of metastasis to the brain or the spinal cord
- Spinal cord compression with back pain and loss of neurologic function
- Bone pain in case of bone metastasis
- Abdominal pain and jaundice in case of liver metastasis
Diagnosis and workup
Since small cell lung cancer is so aggressive, screening for lung cancer is fundamental to identify the disease in an early phase. According to the U.S. Preventive Task Force, screening should be done with low-dose computed tomography, and it is only recommended in adults older than 55 years with a smoking history of 30 packs of cigarettes a year or more. Men who stop smoking should also get screened up to 15 years after quitting. After 15 years of no smoking, the risk is lower, and it is not necessary to screen for lung cancer.
But in the case of a patient with symptoms, they are received by a doctor, and a physical examination is made. The workup to diagnose small-cell lung cancer includes:
- A Complete Blood Count (CBC) with a peripheral smear
- Renal function tests and liver function tests
- Chest radiography
- CT scan of the abdomen and chest
- Magnetic resonance of the brain in case of neurologic symptoms
- Bone marrow aspiration in case of abnormalities in the CBC
After the tumor is located, a biopsy is fundamental to confirm a cancer diagnosis and say what type of cancer it is.
Treatment and prognosis
Small cell lung cancer is an aggressive type of cancer, and treatment should be initiated right away.
There are different modalities of treatment:
- Combination chemotherapy
- Surgical resection
- Spinal cord decompression in case of a compression syndrome
Surgical resection of the tumor is only reserved for patients with no metastasis, and no lymph nodes were taken. The rest of the patients need chemotherapy and radiotherapy. It is also applied to patients with no metastasis after their surgery to destroy any cancer remnants in the lungs or elsewhere.
Radiation therapy is often reserved for the second or third cycle of chemotherapy, depending on how cancer responds to the treatment.
The prognosis of small-cell lung cancer depends on how disseminated cancer is at the moment of the diagnosis. Up to 70% of patients have disseminated disease at the moment of presentation, but not all of them have extensive and very severe metastasis.
Patients with extensive-stage disease respond well to the treatment and survive more than 7 months, but only a few survive for more than 5 years. In contrast, limited-stage disease responds very well to treatment. The survival of over 1 year is expected in 80% of patients, and 15% of them remain alive for more than 5 years.
These patients would have a poorer prognosis if they have a relapse of cancer, if their unintended weight loss is greater than 10%, if they have low sodium levels, and poor general health.
Squamous cell lung cancer: Causes, symptoms, diagnosis, prognosis
Squamous cell lung cancer is a subtype of non-small cell lung cancer. It is actually one of the most common types of carcinoma in the lungs. “Squamous cell” refers to flat cells that make up the air passages throughout the lungs. They used to be epidermoid cells, similar to those found in the skin, but became cancer and now turned into a tumor.
This article will go through squamous cell carcinoma’s essentials and briefly talk about its diagnosis and prognosis.
What is squamous cell lung cancer?
Squamous cell lung cancer is also known as epidermoid carcinoma. It is a frequently-occurring type of NSCLC. 30% of cancer cases occurring in the lung will be squamous cell lung cancer. It develops in the bronchioles and grows more slowly than other lung cancer types, but these patients need to be assessed from an early phase of the disease to figure out the disease stage and what we can do about it.
Squamous cell lung cancer occurs when the abnormal cells of the lung or airways multiply out of control and form a tumor. The tumor can spread to other parts of the body like the brain, liver, and lymph nodes. It is the second more common lung cancer after adenocarcinoma, and it is strongly associated with smoking.
What causes squamous cell lung cancer?
The causes of squamous cell lung cancer are similar to the rest of small-cell lung cancers. The most common cause of is chronic tobacco smoking. It has a solid relationship with smoking all types as cigar, pipe, marijuana, and cigarette smoking.
Secondly, we should list uranium and radon exposition. Actually, uranium miners have a higher incidence of lung cancer regardless of the type. Radon is an inert gas that results from the decay of uranium. Regular breathing in an environment contaminated with radon gas increases the chance of developing squamous cell lung cancer.
Thirdly, we have asbestos exposure as another cause of squamous cell lung cancer. Asbestos is found in our ceiling tiles, fireproofing, and insulation material. People living in this type of building have an increased risk of squamous cell lung cancer.
Other risk factors for squamous cell lung cancer include passive smoking, age, exposure to gasoline, arsenic, talcum powder, family history, and recurring lung inflammation from pneumonia or tuberculosis.
Remember that cancer is a multifactorial disease, and we won’t be able to trace back the exact cause of squamous cell lung cancer in many cases. Instead, we have different risk factors and expositions that may contribute to the formation of a malignant tumor.
Signs and symptoms
Squamous cell lung cancer has several symptoms, and most of them are similar to those found in the rest of non-small cell lung cancer.
One of the most important symptoms is shortness of breath, also known as dyspnea. In this case, there’s a blockage of the airways, and this is mainly the case because squamous cell lung cancer develops in the airways. The second most common symptom is coughing up blood, medically known as hemoptysis. This is also very common in squamous cell lung cancer because the tumor in the airways has abnormal and very fragile blood vessels. Thirdly, pain is also an important symptom, usually located in the center of the chest. Other symptoms can be felt when cancer grows bigger or spreads to other parts.
It is essential to highlight that squamous cell lung cancer tends to give out symptoms earlier than other cancer types. It starts to grow in the lungs’ airways as opposed to different types that start to grow in the edges (for example, adenocarcinoma). Thus, it causes obstruction, bleeding, and other symptoms much faster.
Diagnosis of squamous cell lung cancer
The diagnosis of squamous cell lung cancer is similar to the rest of non-small cell lung cancers. The only difference in diagnosis is that this cancer is more likely to be detected in an early stage. In most cases (up to 75% of patients), cancer will be detected before the tumor has spread to other areas.
These exams can be useful for the diagnosis of squamous cell lung cancer:
- Imaging tests: It is usually enough with X-Rays, and sometimes a CT scan. X-rays show an image traditionally located in the center of the chest in the form of a nodule. Then, a CT scan is performed to evaluate the exact placement of cancer, its relation to nearby structures, the extent of cancer, and any local or nearby spread.
- Sputum cytology: Performing sputum cytology in patients with productive cough can be useful to detect cancer cells and diagnose the type of lung cancer. It may also be helpful to diagnose an infection.
- Tissue sampling: It is a direct biopsy of the tumor using an instrument that goes through the throat and reaches the airways. There are different ways to obtain a biopsy, including biopsies performed as a part of the surgery to treat squamous cell lung cancer.
Prognosis of squamous cell lung cancer
Squamous cell lung cancer sometimes causes Pancoast syndrome. This syndrome is triggered by lung cancers that develop in the upper part of the lungs. As cancer grows, it pushes away other structures, causing pressure upon the nerves, leading to abnormal sensitivity in the upper limbs and shoulders. These patients develop shoulder pain and may report a tingling sensation in the inside of the arms, weakness of the hands, and much more.
The survival rate of squamous cell lung cancer depends on the stage and extent of the tumor. According to statistics, 50% of non-small cell lung cancer patients are still alive after five years if they are detected early. However, new studies and treatments give squamous cell lung cancer a better prognosis than stated in the available literature in 2013.
Prognosis depends on the stage of cancer, the treatment you have, and your comorbidities. So, talk to your doctor to obtain a more accurate understanding of what to expect in your case.
Adenocarcinoma of the lung: Causes, symptoms, diagnosis, prognosis
There are different ways to break down Non-Small-Cell lung cancer (NSCLC) into categories or types. First of all, they divide into large cell carcinoma, adenocarcinoma, and Squamous cell carcinoma.
In this article, we’re briefly going through the essentials of the adenocarcinoma of the lung and what you need to know about its causes, symptoms, diagnosis, treatment, and prognosis.
What is adenocarcinoma of the lung?
Lung adenocarcinoma is a frequently occurring type of NSCLC. It develops in bronchioles and grows more slowly than other types of lung cancer. It takes place when the abnormal cells of the lungs multiply out of control and form a tumor. The tumor can spread to other parts of the body like the brain, liver, and lymph nodes.
It is the most common lung cancer in the United States. It is strongly associated with smoking history. Adenocarcinoma of the lung mostly occurs in the mucosal glands responsible for the secretions and alveoli that help the air in and out of the lungs. 40% of cancer cases occurring in the lung will be adenocarcinoma. Most patients with adenocarcinoma of the lung are under 45 years.
What causes adenocarcinoma of the lung?
The most common cause of adenocarcinoma is chronic tobacco smoking. Smokers are 13 times more likely to develop adenocarcinoma than non-smokers. Smoking includes cigar, pipe, and cigarette smoking.
The second major cause is exposure to radon gas. Regular breathing in an environment contaminated with radon gas increases the chances of developing adenocarcinoma of the lung.
The third major cause is asbestos exposure. Asbestos is found in our ceiling tiles, fireproofing, and insulation material. People living in this type of building have an increased risk of adenocarcinoma of the lung.
Signs and symptoms
Many patients with adenocarcinoma of the lungs have no symptoms. However, it can be diagnosed by X-Rays or a CT scan. We can list a few symptoms typically observed at the last stage of adenocarcinoma:
- Chest pain
- Coughing up blood
- Persistent coughing
- Shortness of breathing
- Poor appetite
- Weight variation
- Raspy voice
Treatment and prognosis
Various tests can be used to diagnose adenocarcinoma of the lung. These are the most important:
Imaging tests include X-rays, magnetic fields, and other technologies that provide a picture from the inside of the body. They are done to determine how far cancer has spread.
- Computed tomography scan (CT scan): A computer tomography scan uses a computer associated with an advanced X-ray machine to get a detailed image from the inside of the body. As compared to simple X-rays, a computer tomography scan provides multiple pictures in different directions. As a result, the location, shape, and size of the mass of the tumor or nodule can be identified.
- Magnetic resonance imaging scan (MRI scan): This imaging test uses radio waves and a magnet, offering a detailed picture of the inside. It is used to determine whether the lung cancer has spread to other body parts such as the spinal cord, lymphatic system, and the brain.
- Positron emission tomography scan (PET scan): This tomography scan is used after a CT scan to confirm the malignant nature of the nodule or mass. It can also be used to determine how far cancer has spread to other parts like bones, the brain, etc. Some hospitals use a combination of CT scan and PET scan known as positron emission tomography-computed tomography scan. The purpose is to diagnose the tumor’s mass in the chest and determine how much it has spread.
One or more laboratory tests can be performed to diagnose or confirm lung cancer, assessing how far it has spread. Standard blood tests such as Complete Blood Count cannot diagnose lung cancer, but they are used to evaluate the organs’ function. The growth of abnormal cells can be diagnosed with other studies:
- Sputum cytology: If someone has deep coughing with sputum production, this test can be performed. The sputum is observed under a microscope to look for lung cancer cells or infection.
- Biopsies: It is also known as tissue sampling. In this case, the doctor performs a biopsy by using an instrument that passes through our throat to the lungs and pinpoints the infected area. The biopsy can be achieved with a closed or open method. Different techniques can be used, including Thoracentesis, Thoracoscopy, a Transthoracic needle biopsy, or a Mediastinoscopy.
Treatment of adenocarcinoma of the lung
There are many approved treatment methods for adenocarcinoma. These include:
- Radiation therapy
- Angiogenesis inhibitors
The treatment chosen method will depend on the patient’s overall health condition and how far it has spread to other organs.
Surgery features the complete removal of the tumor. Three kinds of surgery methods are practiced for the treatment of adenocarcinoma of the lung.
- Lobectomy: In lobectomy, the affected lobe or part of the lung is removed.
- Pneumonectomy: In pneumonectomy, the entire lung is removed. It is practiced when the cancer is in the center of the lung.
- Wedge resection: In wedge resection, only a limited section of the lung is removed. Before surgery, an electrocardiogram and spirometry are carried out to check the health state of the patient.
In radiotherapy, different radiations are applied to destroy cancerous cells. It is practiced if the patient is not a suitable candidate for surgery. The radiations can be directed to the affected part or can be passed with a catheter.
In chemotherapy, different medicines are taken by patients to cure cancer or to shrink it before surgery. This treatment takes place in a cycle, in which drugs are taken for some days, followed by a break period. The number and duration of the cycles depend on the type and extent of cancer spread.
In immunotherapy, medicines are taken to boost up immunity. So, immunotherapy fights against cancer and kills cancerous cells with your immune cells and substances. It is mostly used along with chemotherapy. These medicines are usually given intravenously but can cause fatigue, joint pain, and swelling.
As the abnormal cells develop and grow, they need new blood vessels to supply oxygen to all new growing cells. This process is known as angiogenesis. When the newly developed cells get more oxygen and nutrients, they grow and spread more speedily. Angiogenesis inhibitors can stop the growth of abnormal cells by stopping the development of new blood vessels. Due to insufficient nutrients and oxygen, the cells die, and the growth of abnormal cells slows down. Currently, “Bevacizumab and Ramucirumab” are the two approved angiogenesis inhibitors.
Large-cell carcinoma of the lungs: Causes, symptoms, diagnosis, prognosis
Some clinical entities are not entirely known, and there are many less-frequent variants. When that happens, it is sometimes useful to include the least common variants in a new category, and that is what happens with large cell carcinomas. They are also known as large cell undifferentiated carcinomas, a category of non-small cell lung carcinoma that includes different lung cancer variants that do not enter any other type.
In this article, we’re briefly going through large cell carcinoma, its causes, diagnosis, and prognosis.
What is large-cell carcinoma of the lungs?
In simple words, large cell carcinoma is a category that includes any malignant neoplasm of the lung that is not small cell carcinoma, squamous carcinoma, or adenocarcinoma. This is a very heterogeneous group of cancer, and it is used as a diagnosis of exclusion in the group of non-small cell carcinomas.
Large undifferentiated carcinomas sometimes display similar features to those found in adenocarcinoma or squamous cell carcinoma. Some of them may even have secretory granules and undifferentiated features.
Less than 10% of lung cancer will be large cell undifferentiated carcinoma. The number of cases is dropping lately because new technologies and histologic findings have revealed the true nature of the tumors, detecting more cases of squamous cell carcinoma and glandular carcinoma that were formerly included in this cancer group.
What causes large-cell carcinoma of the lungs?
Large cell carcinoma comprises a very heterogeneous group of lung cancer, and none of them has been widely studied. However, most risk factors and causes of lung cancer also apply to this subtype.
A history of smoking is a common finding in these patients, especially in older adults. In most cases, patients have a duration of the smoking habit of 30 or 40 years before large cell carcinoma shows up. The median age of diagnosis of this type of cancer is 60 years old, and other causes include exposition to radon and passive smoking.
Signs and symptoms
The presenting signs and symptoms of large cell carcinoma are similar to the rest of lung cancers. Some of them are associated with a primary lesion in the lungs. Others are related to spreading inside of the thorax or distant metastasis.
The most common symptoms include cough, chest pain, and hemoptysis (coughing up blood). We can also find changes in the tone of voice, such as hoarseness or a raspy voice. In the case of metastasis, we will also have symptoms such as bone pain and various symptoms associated with the central nervous system depending on the site of the spread.
These patients typically display constitutional symptoms as well. They are unspecific but relate to the severity of the disease. The most common include weight loss, weakness, and loss of the patient’s appetite. In some cases, we can also have fever as a symptom, but it is quite rare.
Large cell carcinoma is a very complex entity, and most cases only give out alarming signs when the disease is very advanced. Thus, it is imperative to evaluate patients as soon as possible if they have a chronic coughing history, even if they are not coughing up blood. If they are older than 40 years and have a positive history of smoking, they should be promptly evaluated to rule out lung cancer.
Persistent pneumonia that does not respond to different antibiotics is also an alarming sign that something is going on. Another sign found in the physical exam is tenderness in the ribs when there is an invasion of the pleura and involvement of the chest wall.
Diagnosis and prognosis
In the diagnosis of large cell carcinoma of the lungs, the first step is considering the patient’s signs and symptoms. It is usually a senior with a chronic cough that has recently started to cough up blood. Chest pain is sometimes present and could be located in any part of the chest.
The first exam to diagnose the disease is a chest radiograph, which shows a large mass in the lungs. This mass can be located in any part of the lung, but it usually occurs peripherally, not in the center of the lung. Other exams can be performed to examine the extent of the mass and define its borders. CT-scans are particularly useful for that.
But diagnosing the type of lung cancer requires performing a histologic evaluation of the lesion after a lung cancer biopsy. It is a diagnosis of exclusion, which means that more common types of lung cancer are ruled out, and if the tumor does not follow the pattern of any of them, the diagnosis of large-cell lung cancer is then considered. That is why it is also known as large cell undifferentiated lung cancer. Since they are relatively more difficult to diagnose, these tumors are usually very large compared to other types. They are attached to the pleura and may start invading other organs in the chest.
The histologic findings often reveal areas of hemorrhage and necrosis of the tissue. They have a solid growth pattern, and their cells have a polygonal or cuboidal form, with large or medium size.
After diagnosing this type of cancer, we can also break it down into different morphologic variants according to what we see in the biopsy:
- Basaloid carcinoma
- Large cell neuroendocrine carcinoma
- Combined large cell neuroendocrine carcinoma
- Large cell carcinoma with rhabdoid features
- Clear cell carcinoma
- Giant cell carcinoma
- Lymphoepithelioma-like carcinoma
There are very few studies of each one of the types above. Thus, the prognosis is sometimes uncertain. It is important to remember that each case should be evaluated individually. Your prognosis will be different depending on your age, the comorbidities, the size and extent of cancer, and the variant. Talk to your doctor about it if you want a personalized answer that applies only to you.
Lung cancer Risk factors
Most people would say that tobacco consumption is the cause of lung cancer, and that is partly true. But only reducing lung cancer risk factors to tobacco smoking would be oversimplifying. There are many others to consider.
In this article, we’re going through the risk factors that increase the likelihood of lung cancer. Some of them can be changed by making adjustments to your lifestyle. Others cannot be altered in any way. And still, others are under active research, and we are still not sure if they increase the risk or not.
Modifiable risk factors
Modifiable risk factors are those that we can change by doing something different or changing something in our lives.
Modifiable risk factors for lung cancer include:
- Tobacco smoking: It is probably the most important modifiable risk factor. 80% of people who die from lung cancer were smokers, and most of them, heavy smokers. Small cell lung cancer is one of the most aggressive types of cancer, and most cases are related to smoking. It is very rare to find one of these cancers in people who have never smoked. The burden of this risk factor is proportional to how frequently you smoke, and the more packs of cigarettes you smoke every day, the greater the risk. Almost all smoking types are directly associated with cancer, including pipe smoking, cigarette smoking, and other variants. Even menthol cigarettes and low-tar cigars have the same effect in increasing the risk of lung cancer.
- Passive smoking: It is also known as secondhand smoke or environmental tobacco smoke because you’re not the one holding the cigarette, but you’re still breathing the smoke that comes out of other people. Thus, the risk of lung cancer in these cases is significantly higher. Secondhand smoking is also a cause of death by lung cancer, and around 7,000 deaths a year are estimated for this risk factor. Passive smoking is a risk factor in families or households where one individual smokes heavily, and the rest become affected by remaining close to him.
- Radon exposure: Radon is a radioactive gas found in nature. It results from uranium decay, and it is impossible to perceive by smell or taste. In the United States, radon exposure is the second cause of lung cancer and the number one cause among nonsmokers. The most dangerous type of radon exposure is found indoors because the airflow typically takes out outdoor exposure. Indoors, radon becomes concentrated, and people breathe this substance without realizing it. Basements can be a source of radon, and it is possible to measure its levels to make sure that we’re not exposed to this substance.
- Asbestos exposure: For many years, asbestos exposure was a concerning problem in houses and buildings. Many houses were made with products that contained asbestos, but current regulations do not allow this. Still, it is used in textile plants, mines, mills, and other occupational sources. Workers exposed to asbestos are more likely than the general population to suffer from lung cancer of a particular type called mesothelioma.
- Other carcinogens exposure: Other carcinogens in the workplace include uranium in radioactive ores, Diesel exhaust, and chemicals such as arsenic, coal products, nickel, silica, cadmium, mustard gas, among others. Industry workers in contact with these and other carcinogens have a higher risk of lung cancer and different cancer types.
- Incorrect supplement use: Not all supplements are beneficial for lung cancer, and vitamin A is a clear example. One would think that the antioxidant properties of beta carotene make it a useful supplement against cancer. But smoking heavily and consuming high beta carotene levels is a bad combination and increases the risk of lung cancer.
Non-modifiable risk factors
This type of risk factor cannot change by a change of habits or a revision of our house and the workplace.
Non-modifiable risk factors for lung cancer include:
- A history of radiotherapy: If you had previous radiation therapy in areas of the chest, the risk of lung cancer increases. The risk is even higher in smokers and people with overlapping risk factors. Radiotherapy in the chest is common in Hodgkin disease, breast cancer, and other types of cancer that involve the chest area.
- Air pollution: This is a common risk factor in populated cities because smog and air pollution work similarly to passive smoking but to a lesser degree. Still, it is a prevalent source of cancer in the population as a whole, and it is thought that 5% of cancer cases worldwide are caused by air pollution.
- Medical history of lung cancer: A previous history of lung cancer increases your risk of recurrence. Another tumor may appear in the same lung or the opposite lung in patients who recovered from the disease. Additionally, the history of lung cancer may not come from yourself. If one of your close relatives had lung cancer, your chances are higher than the average, especially if they developed the disease at a young age. This is probably due to a genetic predisposition to lung cancer, but other aspects also play a role, such as environmental exposure to radon and tobacco smoke.
Risk factors under research
Other risk factors are under active research because we still don’t know if they have a significant role in developing lung cancer.
- Marijuana smoking: Similar to tobacco smoking, marijuana contains tar and other carcinogenic substance found in tobacco. Unlike tobacco smoking, people who smoke marijuana do it all the way to the end of the joint, so they are more likely to smoke the part where tar is more highly concentrated. Moreover, marijuana is inhaled profoundly, and smokers usually keep the smoke inside for extended periods, increasing the lungs’ exposure and the chance of carcinogens deposits in the lung structures.
- Electronic cigarettes: Electronic cigars use an electronic nicotine delivery, and even if they don’t have tobacco, they still don’t have enough research to say if they are harmless or not.
Malhotra, J., Malvezzi, M., Negri, E., La Vecchia, C., & Boffetta, P. (2016). Risk factors for lung cancer worldwide. European Respiratory Journal, 48(3), 889-902.
Akhtar, N., & Bansal, J. G. (2017). Risk factors of Lung Cancer in nonsmoker. Current problems in cancer, 41(5), 328-339.
Living and coping with lung cancer
It seems like everything changes after being diagnosed with lung cancer. Regardless of the stage or the type of cancer, therapy to combat the complications is complicated. There’s also an emotional part of the disease and a social burden that only people with cancer understand.
What can you do about it? In this article, we’re briefly covering what to expect of cancer and coping strategies that will be helpful.
Living with lung cancer symptoms
In some cases, lung cancer does not have apparent symptoms. But most people are diagnosed after they start experiencing problems such as breathlessness, chest pain, and cough.
One of the most common symptoms is breathlessness, and after a while, it can be very frustrating because you have the sensation of running out of breath. But frustration can make it worse. If you want to feel better, try breathing slowly and practice breathing exercises. Remember that you could trigger breathlessness by physical activity, so depending on your condition, you could shop using a trolley or keep your essentials at hand instead of looking for them in different rooms and upstairs. Home oxygen treatment is an excellent option if your condition is severe. If you start experiencing severe breathlessness suddenly and without an obvious trigger, it is essential to report the problem to your doctor because it could be caused by a pleural effusion.
Pain is another common symptom in lung cancer patients, and it is often controlled by medications. But as cancer progresses, pain can become a problem difficult to handle. Palliative care considers the changing nature of cancer pain and makes adjustments accordingly. So, take your medications as instructed and if you feel they are no longer working, talk to your doctor to adjust the dose.
Coping with cancer therapy side effects
Cancer therapy is not easy, and you can go through different side effects that initiate as soon as you start receiving chemotherapy or radiotherapy.
One of the most common symptoms is tiredness or fatigue. You should know that this is a very common problem and not feel bad about yourself because you want to stay longer in bed. Take time to rest and take it easy if you’re doing something that requires moving around too much.
Hair loss and weight loss are also common side effects as the disease progresses or your cancer therapy goes on. These symptoms change your appearance and may affect your self-esteem. Thus, you could talk about it with your loved ones, buy new clothes or use a wig, and talk to a psychologist about it. Weight loss is often countered by a suitable diet created for you, and nurses have a lot of experience in dealing and coping with hair loss.
Emotional and social aspects
One of the first things that change with lung cancer is that you start having more contact with healthcare personnel. You could be assigned a lung cancer nurse, a social worker, and other specialists to help you, and this is sometimes a bit overwhelming. Take one step at a time and use their attention and time to ask your questions and learn about your condition and what happens next.
Lung cancer patients experience a wide range of emotions, including fear, anxiety, depression, and much more. Every patient deals with the situation differently, and nothing is predictable. But being honest with your loved ones and communicating your feelings and emotions is critical to cope with the problem. If you need time for yourself or do not want so much attention, it is alright to say it aloud. Communicate often and assertively.
Talking to others is sometimes an essential part of your therapy. It can be your wife, neighbor, a counselor, or a nurse. Each one of them has a role in your life, and you can communicate different aspects of your experience with them. Different local support groups and organizations can help you find people who understand what you’re going through and speak the same language. But even if you don’t have access to this type of help, talking out your feelings is a way to obtain support from people who love you and want to hold your back.
Money is another critical issue when you’re going through lung cancer. If you’re a provider at home and need to take days off work, financial support becomes a complicated issue. Money problems often trigger more consequences and emotional problems than cancer symptoms by themselves. But there are things you can do to cope with these problems.
Your nurse and healthcare practitioner will help you find out what type of financial support you’re eligible for. For example, if you have a job and need sick leave, you can ask for statutory sick pay. But maybe you don’t have a job and are a candidate for an employment and support allowance. Carers and family members may benefit from a Carer’s allowance, and so on.
Different programs cover different aspects of your money issues. In some cases, you can get free prescriptions if you have an exemption certificate. If you don’t have one and want to apply, you can ask your cancer specialist about it.
Living and coping with lung cancer is challenging and a day-to-day situation. Nobody knows precisely what will happen, so you need to be prepared for uncertainty.
Cancer symptoms are not easy to handle, but drugs and medical support should provide relief. Cancer therapy side effects are sometimes very severe, but they are temporary and often solved with a professional’s help. The situation may seem emotionally overwhelming, but communication and social support from your loved ones will be fundamental to move on. Money problems can be stressful, but you can find solutions according to your finances.
Not everything will have an answer or solution, and you’re entitled to feel sad, angry, or frustrated. But throughout this time, it is vital to identify and adopt coping strategies that will help you go through all of this and improve your quality of life.
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Liao, Y. C., Liao, W. Y., Sun, J. L., Ko, J. C., & Yu, C. J. (2018). Psychological distress and coping strategies among women with incurable lung cancer: a qualitative study. Supportive Care in Cancer, 26(3), 989-996.
Lung cancer metastasis and advanced disease
Cancer is an overgrowth of tissue that occurs in any part of the body when cells lose their capacity to control their division. They become immortal and grow very rapidly. In their advance, cancer cells start losing their properties and become very different from healthy cells. One of the properties they lose is adherence to tissues, so they start migrating to other places. That is what happens in cancer metastasis.
Lung cancer divides into small cell and non-small cell lung cancer. Each one has its own properties, and some of them are more likely to end up in metastasis. In this article, we’re going through lung cancer’s metastasis and what to expect about this disease.
Lung cancer metastasis
Lung cancer metastasis is a very complex process. As noted above, one of the first changes in cancer cells that lead to metastasis is a reduction of cell adherence. These cells are no longer anchored to their surrounding tissue, so they can easily migrate to other tissues.
Many types of lung cancer are detected only when spread to other organs has already occurred. This will be stage IV lung cancer. A stage III lung cancer is also common at the moment of the diagnosis, and this type has spread to the lymph nodes around the tumor. Either way, a complete evaluation is often necessary to rule out spread to distant sites.
The most common metastasis sites after primary lung cancer are the brain, the adrenal glands, and the bones. Different subtypes of lung cancer can spread to other parts of the body. For example, small-cell lung carcinoma commonly spreads to the liver. Adenocarcinoma of the lungs is likely to spread to the brain, especially if they have a mutation in the epidermal growth factor receptor.
The process of migration to other tissues follows this route:
- Tumor growth and cell migration: As noted above, as the tumor grows, its cells become different from the rest and lose adhesion. Cell migration starts, first locally.
- Vascular and lymphatic invasion: At a given moment, cells without adherence properties reach the lymphatics or blood vessels and start circulating throughout the body.
- Extravasation: In this step, cancer cells in lymphatics and blood vessels go through the epithelial tissue and enter a new organ.
- Metastatic focus: In this new organ, cancer cells need to recruit blood vessels and establish themselves to start growing. When they do, a new metastatic focus is created.
Small cell lung cancer, also known as oat cell cancer, is the most common type of metastatic lung cancer. This type grows very rapidly and without giving out symptoms. It usually does not give enough time to diagnose the disease, and 70% of cases are already spread at the moment of diagnosis.
Signs and symptoms
The symptoms of lung cancer metastasis are initially the same as primary cancer. They include shortness of breath, cough, hemoptysis, weight loss, and chest pain. But after a distant spread has occurred, new symptoms are included depending on the site of metastasis.
- In brain metastasis: Neurologic signs and symptoms start showing up, including headaches or blurred vision. Patients may begin feeling weakened and dizzy or start having balance problems. Seizures are also common in distant spread to the brain.
- In liver metastasis: Hepatitis-like symptoms are common in these cases, especially jaundice (a yellowish coloration of the skin). Abdominal pain is found when there are multiple metastasis foci. When the liver function starts to suffer, the organ stops creating essential proteins, and the abdomen begins to swell.
- In bone metastasis: The bone is very susceptible to losing its mineralization, and the effects are similar to those experienced in osteoporosis. Patients are more likely to endure fractures, and bone pain is also common. In some cases, the vertebrae in the spine start to lose their supportive function, leading to spinal cord compression.
- In metastasis to the adrenal glands: These glands synthesize adrenaline, cortisol, and other hormones associated with stress. This increases the patient’s metabolic rate and causes weight loss. Vomiting and nausea are also very common, usually showing up with abdominal pain. Patients often feel very tired and weak.
IF you’re experiencing one of these symptoms, it doesn’t necessarily mean that you have bone cancer and metastasis. Talk to your doctor if you’re worried about your health to get a complete assessment and recommendations adapted to you.
Treatment for metastatic lung cancer
The treatment of lung cancer and metastasis is personalized and different from one patient and the other. When patients are already in stage-4 cancer, achieving a complete cure of the disease is very difficult. Surgery won’t be enough because even if we take out the primary tumor in the lungs, one or many metastases can be found in other parts. There are probably multiple distant metastasis growing, and we can’t see them yet. So, doctors typically use different methods to attack cancer:
- Chemotherapy: It is a standard treatment for metastatic lung cancer. It is a toxic substance that only activates in dividing cells. Since cancer cells have an accelerated dividing rate, they are more likely to be affected. However, chemotherapy can also affect healthy tissue.
- Radiation therapy: They are radiation waves applied directly to the affected area. They have a localized action against cancer and are explicitly directed to the problem area.
- Targeted therapy: This type of therapy is similar to chemotherapy, but it uses certain metabolic properties of cancer to achieve a more targeted effect. You could benefit from this type of treatment depending on the type of cancer and the metabolic properties of cancer cells.
- Immunotherapy: This type of therapy is an immune booster that helps your own immune system to detect and fight cancer more accurately.
In general, metastatic lung cancer has a very poor prognosis. This is very late-stage cancer, and even with the appropriate treatment, the life expectancy can be relatively low. The survival rate of metastatic lung cancer depends on the type of spread.
In distant spread (metastasis to other organs), the 5-year survival rate is 5.8%. If you have a regional spread in the thorax but no distant spread, this number increases to 32%. And if you only have localized spread in the lungs, the 5-year survival rate is 59%.
National Cancer Institute. Cancer stat facts: Lung and bronchus cancer.
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Lung cancer tests and workup
If your doctors suspect lung cancer or need to evaluate your case further, you will probably need many studies in the process. Even after diagnosing and staging lung cancer properly, you still need more exams every now and then to make sure that everything is turning out as expected and detect potential problems before they turn into complications.
The variety of exams and workup tests for lung cancer include different categories, and we’re covering the majority in this article.
The most common imaging study is chest radiography, which typically shows a nodule or mass in one or both lungs. Other findings in chest radiography include enlargement of the mediastinum or helium, atelectasis, and pleural effusions.
When this type of lesion is encountered and follow-up patients with active disease, other studies are recommended. A chest CT-scan is one of the most common and particularly useful for staging. This imaging study can detect lymph node enlargement more accurately and other alterations in soft tissues. Depending on the stage, you might also need a CT scan of the upper abdomen focused on the adrenal glands and the liver, commonly affected by metastasis. A brain CT scan and magnetic resonance is also recommended, but only in patients with neurologic symptoms.
Magnetic resonance of the chest and spinal column is not always necessary unless patients display neurologic symptoms. In these cases, doctors want to rule out spinal cord compression or metastasis in the central nervous system.
But if the main focus is ruling out bone metastasis, one of the best studies is known as bone scintigraphy. This exam evaluates the bone tissue and looks similar to X-rays but highlighting the potential sites of bone metastasis in a darker color.
Similarly, a PET scan is very sensitive to diagnosing malignancies by evaluating the tissues’ metabolic activity. It is helpful to assess solitary pulmonary nodules and other suspicious findings that have not been confirmed yet. This exam is instrumental in searching for metastasis throughout the body, and it is more valuable than a CT scan to evaluate the mediastinum when it is affected by the disease.
Cancer is a multi-organ disease, especially in the late-stage. Thus, laboratory studies are often necessary before and after starting cancer therapy.
A complete blood count is useful at the moment of the diagnosis to evaluate your condition before starting chemotherapy. It is imperative throughout the disease in patients with metastatic lung cancer because one of the metastatic regions is the bone and bone marrow. Thus, metastasis can trigger anemia, neutropenia, and other blood cell abnormalities.
Other important laboratory studies include liver function tests, creatinine, blood urea nitrogen, magnesium, calcium, and serum electrolytes. They provide a valuable prognosis for these patients and help doctors detect paraneoplastic syndromes or suspect a metastasis case.
In emergencies when your breathing is severely affected, an arterial blood gas measurement will help detect and treat respiratory failure and its metabolic complications.
Cytologic studies and biopsies
This study category refers to the analysis of samples under the microscope, which may come from the sputum or a biopsy.
Sputum cytologic studies are not expensive and provide a quick answer in patients with a suspicious nodule or symptoms. However, it does have a very high false-negative rate of 40%. In other words, many patients who actually have lung cancer will have a negative result because their cancer is either not near the respiratory tract or not releasing enough cancer cells to detect them in cytology. For cytologic studies to increase their accuracy, several samples should be taken instead of one, and they should be preserved and processed appropriately.
Another sample taken to the microscope is collected in a needle thoracentesis or pleural fluid cytology in patients with pleural effusion and significant respiratory problems. This method is very sensitive and specific, but having a pleural effusion is by itself an ominous sign of lung cancer, and it is probably a high-risk disease.
On the other hand, a biopsy is usually made through a bronchoscope. Another option in peripheral tumors would be through a transthoracic needle biopsy. Either way, this is a direct sample of the tumor, and it is more reliable. Depending on the technique and the site of the lesion, biopsies can have a variable false-negative rate.
More invasive procedures provide a more accurate assessment of the lesion and direct visualization of the tumor, which helps evaluate the severity of the obstruction and collect tumor samples.
One of the most common invasive procedures in lung cancer is a bronchoscopy, but this procedure is only valuable for central lesions, those located near the airways. When the tumor is located in the periphery and far from the main airways, a bronchoscopy won’t find anything in particular. This procedure is often used to take a biopsy sample.
When bronchoscopy is not applicable, thoracoscopy can help obtain a biopsy sample. This is a minimally-invasive procedure that evaluates the pleura and the outer surface of the lungs. It is a safe procedure with minimal risks.
Tests and workup for special groups
Tests and workup for lung cancer depend on your symptoms and how the disease progresses in your particular case. It also depends on any baseline health problem that you have. Specific populations may need special tests to decide what to do next:
- In patients with metastasis to the central nervous system, a head CT-scan is performed to evaluate the mass and consult the treatment options with the neurosurgeon.
- In immunosuppressed patients, frequent complete blood counts and electrolyte levels are useful to prevent complications
- In patients with intestinal pseudo-obstruction, electrolyte levels are also essential to correct the problem.
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Herbst, R. S., Morgensztern, D., & Boshoff, C. (2018). The biology and management of non-small cell lung cancer. Nature, 553(7689), 446-454.
Lung cancer treatment options and their side effects
Cancer is by far one of the most complicated ailments to treat, and lung cancer is not the exception. Different lines of treatment are available for patients with small-cell lung cancer and non-small cell lung cancer. They depend on the stage of the disease and any complication the patient may have.
This article will briefly discuss the treatment modalities of lung cancer and provide a broad understanding of how each one is selected and its side effects.
In emergency settings, doctors treat cancer according to the symptoms or complications it is causing. The goal is not eradicating the disease but solving the problem that is causing the emergency.
In most cases, emergency in lung cancer is associated with respiratory distress and airway obstructions. The solution may require intubation, admission to an intensive care unit, and procedures such as cricothyrotomy or tracheostomy to obtain easier access to the respiratory tract. Throughout this time, supplemental oxygen is essential to maintain an adequate level of arterial blood gas.
When not in an emergency setting, surgery is the mainstay of treatment in patients with a limited or localized disease. When no spread is found in the mediastinum or any other organ, surgical resection of the mass is performed. Different methods can be used, including lumpectomy when only the nodule is taken out, lobectomy when a complete lobe of the lung is taken out, or pneumonectomy when the totality of the affected lung is taken out. This treatment is only recommended when there is one nodule or multiple nodules in the same lung, and the most common technique is lobectomy.
Before surgery, every patient should undergo a preoperative evaluation to see if surgery is appropriate for them. Their risks are evaluated with studies such as PET, CT scans, and complete blood count. Their cardiopulmonary health is also assessed to see if they are good candidates for surgery.
Besides taking out the tumor, doctors may also need to take out lymph nodes, and this is known as lymphadenectomy. Lymph nodes in the mediastinum are routinely taken out for samples in some cases.
Common side effects of surgery are usually related to wound care and infection. Complications depend on the anesthetics and the cardiorespiratory status of the patient.
In localized cancer, radiation therapy is recommended combined with surgery or when surgery is not a choice due to cardiopulmonary problems and other health conditions. There are different schedules, and each one can be adapted for each patient. For example, it is known that patients with very poor health benefit from a type of schedule known as hyperfractionated radiation therapy. It is also known that complex radiotherapy improves the prognosis in elderly patients who are not candidates for chemotherapy.
There is also adjuvant radiotherapy, which is meant to eliminate traces of the tumor after surgery. This type of treatment is currently controversial, and not all doctors use this approach. Early-stage non-small-cell lung cancer can be treated with stereotactic body radiotherapy, which uses high doses of radiation in 1 or 2 fractions. This allows reducing the side effects and the negative aspects of radiotherapy.
Side effects of radiotherapy are usually localized to the treatment area and include peeling skin, itchiness, reddening, or drying of the skin. It may also cause swallowing problems, shortness of breath, a sore throat, weakness, and fatigue.
This therapy for cancer uses cytotoxic agents that attack cells when they divide very rapidly. Most cells won’t divide as rapidly as cancer, so it should only affect cancer in theory. But other rapidly-dividing cells in the body can be affected too, especially those of the gastrointestinal tract and the bone marrow.
Chemotherapy is usually recommended at some point of the therapy, especially when there’s a relapse of the disease or in cases of metastasis. Adjuvant chemotherapy has an essential role among elderly patients and is often considered in late-stage conditions or when spread to other organs is not confirmed but strongly suspected.
This type of therapy is beneficial for small-cell lung cancer because many non-small-cell lung cancer types are known to be resistant to this approach.
Side effects of chemotherapy include systemic problems such as weight changes, loss of appetite, weakness, and fatigue. It also causes several symptoms associated with tissues that divide rapidly, such as the gastrointestinal lining and the bone marrow. Thus, patients typically exhibit constipation, diarrhea, nausea, vomiting, mouth sores, anemia, and other alteration in their blood.
As we understand lung cancer more thoroughly, it is possible to develop targeted therapy for specific cancer types according to their metabolism. This type of treatment is not available for everyone and depends on the type of cancer you have and particular markers and genetic traits.
Side effects are not as common or severe as in chemotherapy, but they also include dry skin, hepatitis, elevated liver enzymes, and diarrhea.
Management for brain metastasis and spinal cord compression
Metastasis to the neurologic system and bone metastasis that trigger spinal cord compression is more common in small-cell lung cancer due to the aggressiveness of the disease.
In these cases, symptomatic treatment is given to the patient with corticosteroid and brain radiation therapy to destroy metastasis in the brain. If the patient does not yet display symptoms, chemotherapy is preferred, and then radiotherapy can be planned.
In spinal cord compression cases, corticosteroids are also administered immediately to prevent further damage to the affected nerves. Then, management requires surgical decompression of the area, which is often combined with radiation therapy depending on the trigger.
In lung cancer patients, long-term monitoring is essential to reduce the incidence of adverse events and complications. Throughout this period, patients are prompted to quit smoking, eat healthily, and exercise to reduce the risk factors that may further aggravate their condition.
Farago, A. F., & Keane, F. K. (2018). Current standards for clinical management of small cell lung cancer. Translational lung cancer research, 7(1), 69.
Herbst, R. S., Morgensztern, D., & Boshoff, C. (2018). The biology and management of non-small cell lung cancer. Nature, 553(7689), 446-454.
Lung nodules and tumors: Is it lung cancer?
Some of us feel apprehensive or at least a bit worried when entering the doctor’s office. Hearing the word cancer or tumor prompts very negative connotations, and we could even stop listening to whatever the doctor is saying, overwhelmed by fear.
But a tumor is not the same as cancer, and different tumors can develop in the lung. In this article, we’re covering essential tumors and nodules of the lung. Are they the same as lung cancer, or do they carry any particular risk?
Is it lung cancer?
The diagnosis of lung cancer is not that simple. Even if you have a suspicious image in an exam, it is not cancer until it is properly analyzed. The words nodule and tumor are used interchangeably to refer to an image that has not been diagnosed yet. Some of them will be benign tumors. Others will be malignant tumors or cancer. The adjective is only given after a proper diagnosis and exams are performed.
Then, what is a nodule? It is a spot found in imaging tests, usually X-rays or a CT scan. They are very common and often rounded and solid. It can be only one nodule or multiple lesions in the lung.
Many patients have had this type of nodule in the lungs and feel stressed and worried about it only to find out that it is a harmless problem and it won’t turn into cancer. But is there a way to tell benign lesions apart?
How to recognize a benign lung nodule
If a nodule was found in your lung, it is more likely to be benign, especially if you’re a young patient, because lung cancer is only common in the elderly or at least after 40 years. If you do not smoke and have not smoked for the last ten years, cancer risk is even lower. More than that, specific characteristics of the nodule give out clues of a benign nature, especially a small size and the presence of calcium (calcified borders or interior).
Benign nodules are usually asymptomatic. Were it not for this image in the X-rays, you wouldn’t even suspect that something is there in your lungs. Most of them are found by chance when you take an imaging test for any other reason. However, some patients with benign lung nodules have symptoms such as shortness of breath, fever, and coughing. Sometimes they could even cough up blood, and this is not always a sign of cancer.
If these lesions can have cancer-like symptoms and look like cancer, how does the doctor diagnose benign tumors? If you have a very small nodule, one of the approaches could be watching the nodule after repeating the X-rays. A nodule that remains the same size after one or two years is not likely cancer. In some cases, the nodules grow but very slowly. In contrast, cancer tends to proliferate and doubles its size after a few months.
However, this “watch and see” approach may not be appropriate for everyone. It is definitely not a good idea if you have a high risk of cancer (mainly due to advanced age and chronic smoking habits). Thus, additional studies are performed on these patients. The doctor would examine the edges of the nodule, the shape and look for calcifications. Other tests and tumoral markers may be recommended to identify malignant nodules. The doctor may also decide to perform a tuberculosis test because this is a common cause of nodules in the lungs.
In highly suspicious nodules and high-risk patients, a biopsy will be performed. This is an aspirate of cells through a bronchoscopy or using a needle to examine the sample under the microscope. After a close examination, doctors would confirm if the tumor is benign or not.
Causes of benign nodules in the lungs
Nodules in the lungs can grow for different causes, and some are not always diagnosed and understood. However, the most common causes are as follows:
- Infections and inflammation: Tuberculosis is one of the most common infections that cause nodules in the lungs. Others include histoplasmosis, aspergillosis, cryptococcosis, and coccidioidomycosis. In most cases, the immune system tries to destroy the bacteria and causes damage to the lung in the process.
- Lung abscess: An abscess is a collection of pus and debris. They are usually formed as a result of chronic infection. The body encapsulates this infection, causing a round figure in the X-rays.
- Rheumatoid arthritis nodules: This is not a common manifestation of rheumatoid arthritis, but it is still possible. These lesions are usually asymptomatic and more common in patients who use methotrexate.
- Wegener granulomatosis: Wegener’s lung nodules usually measure 2-4 centimeters, but larger nodules can also be found. In most cases, there is more than one nodule, and they are found in both lungs.
- Sarcoidosis: It is often a solitary lung nodule and is commonly mistaken for cancer. This is an inflammatory disease that affects the lymph glands and the lungs.
- Hamartoma: This is also a prevalent cause of solitary lung nodules. But they are filled with lung tissue and not cancerous. In most cases, hamartomas are found in the borders of the lungs, away from the center.
- Bronchial adenoma: Around half of benign tumors in the lungs are diagnosed as bronchial adenomas. They are growths of tissue, but they are not malignant. They develop in the ducts and mucous glands of the airways.
- Fibroma or lipoma: These tumors are not as common as the others on the list
- Lung cysts and birth defects: A cyst is a lesion filled with liquid. This and other types of lesions can be found as birth defects.
Treating benign tumors in the lungs
Benign tumors in the lungs do not require aggressive treatment as cancer does. Some of them are not treated at all. Instead, doctors decide to watch the nodule and take new imaging tests after a while to compare.
Depending on the case, the doctor may recommend taking a biopsy or removing the tumor entirely. After a benign nodule in the lungs is diagnosed, your treatment will be limited to the underlying disease. For example, if you have tuberculosis or pneumonia, you will likely need a round of antibiotics.
Ohtsuka, T., Nomori, H., Horio, H., Naruke, T., & Suemasu, K. (2003). Radiological examination for peripheral lung cancers and benign nodules less than 10 mm. Lung Cancer, 42(3), 291-296.
Zhang, G., Yang, Z., Gong, L., Jiang, S., & Wang, L. (2019). Classification of benign and malignant lung nodules from CT images based on hybrid features. Physics in Medicine & Biology, 64(12), 125011.
Loverdos, K., Fotiadis, A., Kontogianni, C., Iliopoulou, M., & Gaga, M. (2019). Lung nodules: A comprehensive review on current approach and management. Annals of thoracic medicine, 14(4), 226.
Pabón Páramo, C. A., Antúnez Oliva, J. A., & Montero Brenes, F. F. (2020). Solitary pulmonary nodule: radiological characterization. Revista Médica Sinergia, 5(03), 399-399.
Prevention of lung cancer
Prevention is the best cure possible. It is an action taken before disease to reduce our risk, in this case, of getting lung cancer. Cancer prevention reduces the death toll and the complications of the disease. One way to do it would be recognizing the risk factors and changing our predisposition. Another way would be finding protective factors and adopting them to reduce the risk.
Lung cancer is very dangerous because the lungs are in contact with a large volume of blood. Thus, the chance of metastasis is very high, especially in small cell lung cancer. Therefore, instead of solving the problem when it shows up, it is wise to reduce the risk of this leading cause of death worldwide.
In this article, we’re going through quick facts about lung cancer prevention. We’ll cover risk factors and how to make changes in them. We’ll also cover additional steps you can take to reduce your risk of lung cancer.
Changing your modifiable risk factors
Risk factors divide into modifiable and non-modifiable. You can change the former, but you can do nothing about the latter. The first step to prevent lung cancer is to avoid the modifiable risk factors or change your habits to protect you instead of putting you at risk.
These recommendations will help you identify and change your risk factors to avoid lung cancer:
- Stop smoking: Tobacco smoke is one of the leading causes of lung cancer. Most cases of aggressive small cell lung cancer had a history of smoking heavily or for many years. The best way to prevent this disease is simply to stop smoking. This applies to patients with active or past lung cancer, too. To stop smoking, patients can use nicotine replacement products and go through the withdrawal period with antidepressants and anxiolytics. If you need help to quit smoking, do not hesitate to talk to your doctor. The risk will not be reduced immediately. Instead, it will start declining gradually, and in 10 years no smoking, you will have up to 60% lower chances of lung cancer.
- Be careful with secondhand smoke: This is one of the most common risk factors in patients who do not smoke. If they live in a household where people smoke heavily, they often smoke passively. Air filters and purifiers can reduce the risk of secondhand smoke in these cases by taking away the particles of smoke in your room despite living in a house of smokers.
- Report to your doctor if you have a family history: Family history is important, especially if your close relatives have lung cancer at a young age. People with lung cancer usually smoke and have genetics and habits in common with you. Thus, your risk could be invertedly higher as compared to the average. It is wise to share this data with your doctor if he didn’t ask you before. This way, he will decide when to start screening you for lung cancer according to your risks.
- Avoid radiation and radon sources: Radiation and radon are both causes of lung cancer. You don’t need to reject getting X-rays or an MRI because these diagnostic tests are not associated with high cancer risk. If they were, they would not be used in medicine. They are only dangerous if you work in a hospital’s imaging department and receive these radiations all day without protecting yourself. Radon exposure is more pervasive in our daily lives, and we can be exposed to this natural radioactive gas without even realizing it because it doesn’t smell or look any different. You can measure radon levels in your house, workplace, and other places where you’re currently passing your time.
- Consider your workplace risk: Companies should assess workplace risks to reduce the incidence of cancer and other diseases. If you work with substances such as chromium, asbestos, nickel, and arsenic, you need to use your full protection.
- Use supplements wisely: Not all supplements are harmless, and you need to talk to your doctor before starting any new supplements. Lung cancer is an example because who would say that an antioxidant can speed up cancer? But that is what happens with vitamin A in smokers. Taking vitamin A supplements and smoking heavily is a terrible idea. The supplement can increase your risk of lung cancer instead of lowering it down. This trend is only found in active smokers. Non-smokers won’t increase their risk of lung cancer with vitamin A.
Additional steps to take
The recommendations above are beneficial to identify and change the most important modifiable risk factors. You can also consider these recommendations to lower the risk further:
- Follow a healthier diet: There is evidence that eating plenty of fruits and vegetables reduces the risk of all types of cancer, including lung cancer. Many doctors recommend a healthy and varied diet to reduce the risk of this and many other ailments. However, the diet changes according to our culture, and it is a bit difficult to control the settings, so the evidence presented so far is often not enough.
- Increase your physical activity levels: A sedentary behavior is known to increase the risk of lung cancer, and studies show that living a more active life can lower the risk. The recommendation is to increase your physical activity levels with a minimum goal of 30 minutes a day for 5 days a week.
- Be in contact with your doctor: It is also essential to stay in touch with your doctor and inform if you start having respiratory symptoms. There is also secondary prevention which reduces the risk of complications in patients who already have a disease. If you detect cancer early in the course of the disease, the life expectancy will be much higher, and your doctor will have more time and resources to help you.
Burns, D. M. (2000). Primary prevention, smoking, and smoking cessation: implications for future trends in lung cancer prevention. Cancer, 89(S11), 2506-2509.
Cruz, C. S. D., Tanoue, L. T., & Matthay, R. A. (2011). Lung cancer: epidemiology, etiology, and prevention. Clinics in chest medicine, 32(4), 605-644.
Schachter, E. N., & Neuman, T. (2007). Targeted therapies for the prevention of lung cancer. Drugs of Today, 43(12), 897-936.
Frequently Asked Questions about Lung Cancer
Are lung cancer symptoms intermittent or constant?
Lung cancer symptoms include cough, chest pain, coughing up blood, and shortness of breath. These symptoms are usually progressive and become worse as the tumor keeps on growing. This is a chronic disease, and the symptoms are kept for a long time. However, there is variation between one patient and another in how they experience symptoms. Coughing up blood and shortness of breath can be intermittent symptoms, but the cough is usually constant, especially in patients with lung cancer and smoking habit.
Intermittent symptoms sometimes give patients the wrong idea that their problem is not severe. But after a while, and when the tumor grows bigger, the symptoms become constant and very intense. We don’t want to wait until that happens to do something about it. That’s why it is so important to talk to your doctor about new respiratory symptoms, especially if you have a long history of tobacco smoking.
Are lung cancer and colon cancer-related?
Lung cancer and colon cancer are both common malignancies. They share similar risk factors, and it is widely accepted that having cancer in one part of the body increases the risk of cancer or metastasis in another part of the body, even distant organs.
In some cases, doctors can find primary lung cancer and primary colon cancer simultaneously in the same patient. The word primary means that neither of them is metastasis. They are independent forms of cancer developing in different parts of the body. This is known as synchronous colorectal and lung cancer, and it is not common.
Cases have been reported in literature reviews, and most of them are heavy smokers, which explains the association between colon and lung cancer with high exposure to carcinogens. However, even in heavy smokers, synchronous colorectal and lung cancer is uncommon. The most common gastrointestinal cancer in relation to lung cancer is esophageal cancer and other types developing near the airways.
Are lung cancer rates decreasing or increasing?
In the early 1900s, lung cancer was somewhat rare, but as the years went by and medicine progressed to diagnose the disease, lung cancer became prevalent. Reaching the end of the 20th century, lung cancer was one of the most common causes of preventable death in many developed countries. More recently, it has become the most common cause of death related to the habit of smoking.
The disease rates are increasing, and this is not only because we have more lung cancer cases. We have also developed new technologies to detect lung cancer and treat the disease at an early stage. Thus, the fact that lung cancer is more commonly diagnosed is both good and bad news.
Is lung cancer curable?
Curing lung cancer depends widely on the stage, the moment of diagnosis, and the health conditions of the affected patient. Only early-stage cancer is curable through surgical excision of the tumor, followed by radiotherapy or chemotherapy, depending on the case. Late-stage cancer is more difficult to treat, and most patients do not achieve a complete cure.
However, even early-stage cancer can be difficult to cure sometimes when patients are affected by severe health problems that do not make them candidates for surgery. Thus, every patient should be evaluated individually, and the answer to this question depends on too many factors and the uncertain nature of cancer.
Can lung cancer spread to the brain?
Late-stage lung cancer loses its adherence to the surrounding tissue, and these malignant cells start to break apart from the primary tumor. As they do, lung cancer starts to spread, first locally in the opposite lung and nearby structures. Then, it spreads to other organs, and some of them are very distant. This is known as metastasis, and it is only found in advanced cancer.
The most common metastasis in lung cancer migrates to the bone tissue, the liver, and the adrenal gland. Metastasis to the nervous system is more common in small-cell lung cancer, which is more aggressive and is usually related to tobacco smoking.
However, metastasis to the nervous system is only suspected when patients start displaying neurologic signs and symptoms. It is not common in adenocarcinoma of the lungs and other types of non-small cell lung cancer.
Can lung cancer cause back pain?
As the primary tumor spreads in lung cancer, it starts affecting nearby organs and then distant organs, too. In some patients, lung cancer pain is located on the chest but also radiates to the upper back, especially when cancer grows larger and starts creating pressure on the chest.
In patients with lung cancer and metastasis, back pain is also a possibility. It happens because they have metastasis to bony structures of the spine. The affected vertebrae lose their bone mineralization and start to break apart. The pain is similar to that experienced by people with osteoporosis. More severe pain can be experienced by patients who develop a compression syndrome if their vertebrae slip and start pinching the adjacent nerves.
Can lung cancer cause anemia?
Lung cancer causes many other health problems as the tumor keeps on growing. The lungs are deeply involved with blood vessels and perform the function of oxygenation, so it is reasonable to think that lung cancer causes anemia. However, the frequency of anemia cases in lung cancer depends on the tumor stage, the patient’s treatment, and many other aspects of the disease.
Overall, many patients with lung cancer also have anemia at the moment of the diagnosis. They need to be treated with hematopoietic growth factors, vitamins and minerals, and sometimes blood transfusions. Anemia is also common as a result of radiation therapy or chemotherapy in patients with lung cancer.
The reason is deeply involved with the invasion of bone tissue and the bone marrow by metastasis or an impairment of the same structure by chemotherapeutic agents. Sometimes lung cancer leads to metastasis in the gastrointestinal system, causing risk of perforation and gastrointestinal bleeding and nutrient absorption problems that lead to anemia.
Can a blood test detect lung cancer?
The most reliable way to detect blood cancer is by looking at imaging studies, especially a CT-scan. However, new studies are being developed to detect lung cancer markers in the blood. One of them is called Lung-CLiP, and it is detected in the blood. According to research, it could help identify 40-70% of cases of early-stage cancer in high-risk patients. However, it is essential to remember that this is only a blood marker that is under clinical trials, and it is not yet a standardized blood test to detect lung cancer.
Blood tests are essential in the diagnosis of lung cancer, but not because they detect a tumor. A blood test provides helpful insight into how cancer is affecting the rest of the body and gives doctors information to be used in the treatment protocol. It also offers a valuable prognosis because electrolyte alterations and hypercalcemia are known markers of a bad prognosis.
Can lung cancer cause high blood pressure?
Lung cancer spreads to different organs, and one of them is the adrenal glands, located above the kidneys. The adrenal glands release adrenaline into the blood, and this hormone is known to increase the heart rate and blood pressure. Thus, metastatic lung cancer can trigger high blood pressure when it takes the adrenal glands. This elevation of blood pressure should be evaluated in different settings because sometimes lung cancer patients feel apprehensive and nervous in the doctor’s office, which naturally increases their blood pressure without any metastasis.
It is also useful to differentiate high blood pressure from arterial pulmonary hypertension, which is more common in lung cancer. This is basically hypertension inside of the lungs, and it typically affects one lung. Pulmonary hypertension can cause edema, shortness of breath, and other signs and symptoms common in lung cancer. It involves the heart function indirectly and may lead to cardiovascular complications.
What type of lung cancer is caused by smoking?
The most common cause of lung cancer is smoking because tobacco smoke contains thousands of carcinogens and other substances that induce inflammation and other lung tissue changes. Most cases of cancer are related to smoking, but not all of them. These patients have in common that most of them develop more aggressive diseases and their cardiorespiratory comorbidities are far worse. It is more likely to find complications and late-stage disease in smokers.
The most aggressive type of lung cancer is known as small-cell lung cancer. More than 70% of patients with small-cell lung cancer had a smoking history and are diagnosed when the disease has reached a late stage. Smoking can also trigger other types of cancer, such as adenocarcinoma of the lung. But the most common type of lung cancer caused by smoking is small-cell lung cancer. It is also one of the most dangerous types of lung cancer.
What type of lung cancer is caused by asbestos?
Asbestos is associated with a high risk of a type of cancer known as mesothelioma. Given the current legislation, asbestos is not commonly used in construction work, and mesothelioma incidence is infrequent. This type of cancer forms in the lining of the lungs, known as the pleura. It can also lead to cancer in the heart, abdomen, and other organ linings.
Mesothelioma does not appear precisely in the lungs but the external lung coating. It scatters throughout the mesothelial lining and all around the lungs instead of forming a mass or nodule. This type of cancer frequently spreads to other parts of the chest and does not always metastasize.
How does lung cancer look like?
In most cases, lung cancers are visually apparent in X-rays or a CT-scan, and that’s how doctors diagnose the disease. In the chest X-rays, it looks like a mass or nodule in the lungs. It may look like a black or white spot on your lungs, depending on the type of cancer and the stage. An interesting feature is that lung cancer does not have calcifications, which look like white strings in the X-rays.
Your doctor will obtain a more detailed look at the lesion and the surrounding areas in a CT scan. Cancer is usually irregular and spiculated. It looks abnormal in most imaging tests.
Under the microscope, lung cancer looks very different from healthy tissue. As the disease progresses, the cells lose their characteristics and become more and more abnormal. They have varying shapes and sometimes more than one nucleus. They lose their capacity to adhere to tissues and start migrating to other parts of the body.
When does lung cancer spread?
Lung cancer only spreads in an intermediate to late stage of the disease. In the initial phase, tumor cells are similar to healthy cells, and the main difference is the rate of cell division. As the tumor keeps growing, more mutations overlap, and the cells start losing their properties. One of these properties is adhesion to the adjacent tissues. Adhesion prevents cells from traveling to other parts of the body. Instead, they stay in place in the tissue they are assigned to.
When cancer cells lose their adhesive capacity, they are easily broken down and dispersed in the adjacent tissue. Thus, one of the initial spreads is localized in the cancer’s vicinity, especially in the lymph nodes and nearby tissue. As cancer keeps growing and the cells lose more properties, it starts to travel through the lymphatic system and the blood to other structures such as the bone, the adrenal glands, and the brain.
Does lung cancer come back after treatment?
Recurrence is the name of cancer that comes back after being apparently cured by cancer treatment. This happens to any type of cancer, and it does not mean that your doctor was careless or did something wrong. Even patients who follow a strict treatment protocol can have a recurrence.
This happens for many reasons. One of them is resistance to treatment by cells that were spreading from the primary tumor. They could display different mutations that were not sensitive to the type of therapy you were receiving and took away the primary tumor. Thus, recurrent tumors sometimes develop in the same lung, the opposite lung, or in another organ.
Another possibility is that you were diagnosed with apparently early-stage cancer, but nobody knew that it was already spreading. Localized cancer was treated appropriately, but the spreading cells were not considered in the treatment protocol.
Where is lung cancer more common?
Lung cancer can be localized in different parts of the lungs. There are basically three sections of the lungs: the central part, the peripheral part, and the pleura. In the central part of the lung, we can find the upper airways and their branches. In the peripheral portion of the lungs, we have spongy tissue without major airways. The pleura is the lungs’ outer lining, and it is in close contact with the chest wall, the mediastinum, and other structures.
The most common location of lung cancer depends on the type. Small cell lung cancer is a more aggressive type, and it can be located in the peripheral part of the lungs. Since it doesn’t directly contact the airways, patients do not cough or have obstructive symptoms until cancer has already grown bigger. Other types of cancer are easier to detect because they are located in the center of the lungs, and they are also more common.
Where is lung cancer pain located?
Lung cancer does not always cause pain, or at least not in the early stages of the disease. But when it causes pain, it is usually located near the trouble area. It is typically close to the primary lesion. In some cases, lung cancer causes pain in the airways, especially in patients with chronic cough. So, you could also have a sore throat.
The pain is not always felt in the chest. In some cases, it can be felt in your shoulders or your back. It all depends on what part of the lungs is taken by the disease and what nerve terminals it is affecting. It may or may not get worse when you cough or sneeze, and it can be intermittent, constant, sharp, or dull.
Which lung cancer is worse?
Lung cancer is never a good diagnosis, but lung cancer types are typically more aggressive than others. Small cell lung cancer is one of them. This type of lung cancer develops in chronic smokers, and it is one of the most aggressive types. One of the problems of small-cell lung cancer is that it won’t cause any symptoms at the early stage of the disease. This is especially true in cancers located at the lungs’ periphery because they are not in close contact with the airways.
Small-cell lung cancer is usually diagnosed when the disease has already advanced. Most of these patients have aggressive cancer that already spread to other tissues inside the thorax and other distant organs. Small-cell lung cancer also has a worse prognosis, especially at the late stage of the disease.
Why lung cancer causes pleural effusion and cough?
Each symptom of lung cancer has an explanation. Cough is perhaps one of the easiest to explain, mainly when cancer is located near the airways. There’s an inflammatory process going on around cancer, and the airways start to create a lot of mucus. Mucus clots are formed, and the lungs try to eliminate them by coughing. There is also a destruction of the lining of the airways and debris formation that the body tries to eliminate by coughing.
Pleural effusion is fluid that collects around the lungs. It starts to accumulate when the lungs’ periphery is affected by the tumor and when it spreads to the pleura. There is a little bit of fluid in the pleural space, but when cancer cells develop in this area, they increase the production of this fluid and may reduce its absorption by blocking the liquid’s regular draining. Other types of cancer also cause pleural effusion by similar causes, including breast cancer and lymphoma. The most common type of cancer associated with lymphoma formation is mesothelioma.
Why lung cancer causes weight loss?
Lung cancer is in close contact with a massive amount of blood every second and robs many nutrients and oxygen from the blood. It consumes a lot of energy to keep creating new cells and dividing. This creates a significant metabolic burden and increases the calories we spend at rest. So, even when you’re not exercising, cancer takes up extra calories as if you were doing physical activity.
Additionally, some patients with lung cancer experience a reduction in appetite levels. They are consuming fewer nutrients and calories while burning extra calories at rest. Thus, they are more likely to lose weight as the disease progresses.
Why nonsmokers develop lung cancer?
Tobacco smoking is only one risk factor for lung cancer, but it is far from being the only one. Radon exposure, radiation, asbestos, and many other risk factors may also contribute. You may not have any of these risk factors and still grow lung cancer if you have a genetic predisposition. Smog and contamination can also contribute to lung cancer.
A common reason for lung cancer in nonsmokers is secondhand smoke, especially if you live or work with people who smoke. Thus, if you spend a lot of time at work or at home with smokers, it would be a good idea to buy an air cleaner, which takes out secondhand smoke and reduces your risk of lung cancer.
If you want to evaluate your personal risk for lung cancer or feel worried about having smokers at home or family members with the disease, talk to your doctor to see if you’re a candidate for lung cancer screening and what you can do about it.