Can You Survive Stage 4 Lung Cancer

Can you survive stage 4 lung cancer?

The life expectancy or survival rate of cancer is the first question that comes to any person diagnosed with lung cancer, and when it is stage 4 lung cancer. According to the National Cancer Institute (NCI), lung cancer accounts for about 12.4% of all the new cases that are being reported in today’s time. Thus, with the increasing cases of lung cancer diagnosis, it is important to look at its survival rate at different stages. In this article, let us talk about the survival rate of stage 4 lung cancer.

What are the characteristics of stage IV lung cancer?

Lung cancer is classified into several stages as per the severity of the disease. The doctor chooses the appropriate treatment on the basis of the NSCLC staging based on the expected outcome and prognosis. The TNM classification system is used to determine the different stages of lung cancer. The classification system categorises disease severity based on three parametres:

T: The size and extent of the primary tumour
N: Whether or not the nearby lymph nodes are affected with cancer cells
M: Whether or not distant metastasis has occurred

In stage IV lung cancer, the extent of metastasis and prognosis may vary. Thus, stage IV of non-small cell lung cancer (NSCLC) is broken down into two subcategories.

Stage 4a lung cancer: This stage is characterised by malignant effusion, that is, cancer spreads to other parts like:

Within the chest
Chest of the opposite lung
Lining surrounding the lungs
Lining of the heart
Fluid surrounding the heart or the lungs

Stage 4b lung cancer: In this stage, cancer spreads to one or more distant organs as well like adrenal gland, liver, distant lymph nodes, brain, and bone.

What are the survival statistics of stage IV lung cancer?

Generally, the five-year survival rates are used to calculate the stage 4 lung cancer survival rates. The five-year survival rate estimates the percentage of people who will survive for at least 5 years after they are diagnosed with stage 4 lung cancer. There are two ways in which the survival rate can be calculated.

Lung cancer stage 4 survival rate by TNM stage

The extent of prognosis and metastasis of stage 4 lung cancer plays an important role in predicting the survival rate of lung cancer. The 1-year survival rate of patients with stage IV lung cancer is between 15% to 19%. The 5-year survival rate of stage 4a lung cancer is around 10%, whereas, for stage 4b lung cancer, the survival rate is less than 1%.

Lung cancer stage 4 survival rate by disease extent

According to the Surveillance, Epidemiology, and End Results (SEER) program by the National Cancer Institute calculates the survival rate on the basis of the extent of lung cancer in your body. The three main categories in which lung cancer stage 4 are classified by the SEER system are:

Localised: The cancer is limited to your lungs.
Regional: The cancer has spread to nearby lymph nodes or structures.
Distant: Metastatic cancer

In the SEER system of classification, stage 4a and 4b lung cancer belong to the same category. The melded category of stage 4 lung cancer reduces its 5-year survival rate to 5.8%. This system does not take into account the huge variability in the survival rate of stage 4 lung cancer, especially in people with limited metastasis.

SEER stage of lung cancer	Percentage survival rate
Localised	61.2%
Regional	33.5%
Distant	7.0%
Unstaged	9.9%

What are the factors that influence the survival rate of stage IV lung cancer?

The variations in the survival rate of lung cancer stage 4 indicate that there are no two people that have the same disease; that is, stage 4 lung cancer is not the same in all patients. Multiple factors influence the survival rate of stage 4 lung cancer, unlike other stages of lung cancer. Some of these factors can be modified, while others are non-modifiable factors.

Age

The outcome of lung cancer treatment in India decreases in older people, especially after the age of 70, irrespective of the stage at which the cancer was diagnosed. This is because, for people above 70 years of age, general poor health and a weakened immune system reduce the potential to suppress the growth of the tumour. An increased age affects both the progression of the disease and stage 4 lung cancer survival rates as well. A 50-year-old person has a greater chance of surviving for the next 5 years after a lung cancer diagnosis at stage 4 than a person at the age of 65. The stage 4 lung cancer survival rate by age based on the stage at diagnosis is tabulated below as per the data obtained from SEER.

Stage at diagnosis	Age less than 50 years	Age between 50-64 years	Age above 65 years
Localised	86.7%	69.8%	56.9%
Regional	51.3%	38.9%	29.9%
Distant	14.2%	8.7%	5.6%
Unstaged	38.4%	18.3%	7.1%

Gender

Not only males are at a higher risk of developing lung cancer but are also more likely to die of cancer than females. It is generally observed that males have comparatively poorer outcomes of lung cancer treatment than females. The 5-year survival rate of females is 27%, and at stage 4 the survival rate is 8.6%, while for males, the survival rate is 19.2%, and the 5-year survival rate is 5.6%. This is because of the genetic disadvantage that these men have. Men are less prone to have treatable gene mutations, which the recent targeted therapies can treat for stage 4 lung cancer.

Performance status

The stage 4 lung cancer survival rate also depends on your performance status (PS). PS refers to your ability to function in everyday life. PS can be measured in several ways. According to the Eastern Cooperative Oncology Group (ECOG), the PS is rated from 0 to 5 where 0 indicates fully functional everyday life and 5 indicates death. The 5-year survival rate of stage 4 lung cancer based on performance status is tabulated below.

Performance status	5 year survival rate
0	45.9%
1	18.7%
2	5.8%
3	0%
4	0%
5	NA

Smoking status

Smoking is an important modifiable factor that can reverse your stage 4 lung cancer treatment results. It has been observed in research published by the Brazilian Journal of Pulmonology that if you quit smoking before your chemotherapy sessions start, you can increase your survival rate by 6 months.

At the end

Stage 4 lung cancer is a critical stage. Lung cancer at this stage is incurable. Yet, this does not mean survival after lung cancer is not possible. The current treatments for stage 4 lung cancer focus more on delaying the progression of cancer, minimising its symptoms, and improving your quality of life. Now that you know the survival rate of stage 4 lung cancer and the factors affecting the rate make sure that you eliminate the modifiable factors for better survival.