Could Genetics Be The Reason Some Smokers Don't Get Lung Cancer?

According to the American Cancer Society, lung cancer is one of the most common forms of cancer and the number one cause of cancer-related deaths. It is estimated that almost 237,000 cases of lung cancer will arise in the United States this year with over 130,000 deaths, per the American Cancer Society. The American Lung Association states that up to 90% of lung cancer deaths are due to smoking.

Signs of lung cancer may include a persistent cough, wheezing, and a hoarse voice as well as coughing up blood, chest pain, and a loss of appetite (via Medical News Today). If you are 55 or older with a history of smoking, your doctor may suggest regular screenings through a CT scan to check for any abnormalities in your lungs, per Medical News Today. If your screening indicates that cancer in your lungs may be present, your doctor will most likely order additional testing for you in the form of an x-ray, MRI, or biopsy, per Medical News Today.

While you have a much higher likelihood of dying from lung cancer if you smoke, new research shows that not everyone who smokes will in fact develop lung cancer. The reason for this may have to do with your DNA.

A 2022 study published in Nature Genetics looked at the cells lining the lungs of 33 participants, 19 of which who smoke and 14 who do not. The cells that were examined were more likely to mutate in the group who smoked, highlighting the fact that smoking increases a person's chances of developing lung cancer, according to researchers (via WebMD).

The smokers in the study were classified by their "pack-years". According to Verywell Mind, a pack-year determines the duration and frequency in which somebody smokes. For example, smoking 20 cigarettes per day for one year is equivalent to one pack-year, per Verywell Mind. While the study initially linked a higher number of pack-years with more cell mutations, this trend plateaued after a person hit 23 pack-years, indicating that the genes of some smokers help to protect them against additional mutations, via WebMD.

Study author Dr. Simon Spivack explained to WebMD, "The heaviest smokers did not have the highest mutation burden. Our data suggest that these individuals may have survived for so long in spite of their heavy smoking because they managed to suppress further mutation accumulation."