Is Lung Cancer Hereditary? Understanding Your Family Risk

 

Lung cancer is the most common cancer worldwide, and it is also one with a high mortality rate. While smoking remains the leading cause, many people wonder whether lung cancer can also run in families. The answer is yes; lung cancer can have a hereditary component, although it’s not as straightforward as with some other cancers, like breast or colon cancer.

Genetic Factors and Family History

If you have a parent, brother, or sister who's had lung cancer, you're two or three times more likely to get this cancer than someone without a family history of the condition. But you need to put that risk in perspective. Your overall risk is still very low. 

Having a parent or sibling with lung cancer doesn't mean you'll get the disease. Only about 8% of lung cancers run in families.

Researchers have identified certain gene mutations that may predispose someone to lung cancer. For example, changes in the TP53, EGFR, and ALK genes have been linked to an increased risk. 

Some people inherit genetic traits that affect how their bodies process tobacco smoke or repair damaged DNA, which may also contribute to cancer development.

Genes and Lung Cancer

A small number of lung cancers are linked to genes. Genes are pieces of DNA that carry the instructions your body needs to work. Genes control how your cells grow, divide, and die.

There are several genes in our body whose job is to prevent the growth, development, and multiplication of abnormal cells in the body.

The proto-oncogenes regulate cell growth and division. Tumor suppressor genes stop cells from dividing or make them die off when you don't need them anymore. Changes called mutations in these genes allow cells to divide and divide until they form tumors. That's how cancer starts.

Some gene mutations make it harder for your body to get rid of cancer-causing chemicals. Others prevent damaged DNA from repairing itself.

Most gene changes that raise lung cancer risk happen during a person's lifetime. Rarely, someone inherits these mutations from their parents.

Genes are more likely to cause some types of lung cancer than others. For example, about 60% of people with lung adenocarcinomas have certain gene mutations.

Other Factors Causing Cancer in Families

If lung cancer runs in your family, genes may not be the only reason. A shared environment can also be part of the risk. For instance, if someone in your home smoked, that could put you at risk. The same is true if you and your family were exposed to the same cancer-causing chemicals.