What are the investigations to find the familial risk of lung cancer?

Hello,

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Lung cancer occurring at 28 years is unusual, and he is right to be concerned regarding familial risk. As far as lung cancer is concerned, there is no specific gene or syndrome which is considered familial. But studies have shown that if a family member who had lung cancer and was a non-smoker, the risk of lung cancer in them is high.

There are genetic tests available that can detect such mutation and their risk of causing lung cancer. But these tests should be done in a patient who had cancer so we can identify the particular mutation. So that the relatives could be tested for the specific mutation. The most widely known mutation in such cases is EGFR (epidermal growth factor receptor), which can cause familial lung cancer.

If his sister was tested for this and it was negative, then there is no further need for testing. So even if we do the test in your friend and find some abnormalities, we will not be sure of their significance. It will only add to the anxiety of your friend.

What I would recommend right now is to adopt a healthy lifestyle and avoid known risk factors for lung cancer. As some researchers have shown that family history makes you seven to eight times more prone than a normal person if you continue to smoke.

Also, if possible, I would like to see the histopathology report of his sister regarding type.

Hello,

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There is no model that can calculate individual risk based on family history. So, I can only give you the value based on population data. Positive family history will increase risk by one to two times.

EGFR (epidermal growth factor receptor) mutation is tested in the patient and tumor biopsy samples. If a particular mutation is detected, we see whether it has any hereditary capacity.

Right now, we do not know which EGFR (epidermal growth factor receptor) mutation to test. Even if your friend comes out to be positive, we do not know whether his sister had the same mutation and whether this mutation was the cause of lung cancer. Even in the normal population, you will have some mutations. This will just add to the cost and patient anxiety.

Further, there is currently no drug to prevent the outcome other than lifestyle change and avoidance of risk factors. So as per guidelines, I will not recommend mutation testing for him.