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.
References:
National Institutes of Health. (2016). SEER stat fact sheets: Lung and bronchus cancer. Rockville, MD: National Institutes of Health.
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