Smoking is a huge risk factor for lung cancer — but it’s not the only one.
Researchers have found an alarming trait that can skyrocket a person’s risk of developing this deadly disease.
Surprisingly, it has nothing to do with cigarettes and everything to do with genetics.
According to a new study, a rare inherited germline mutation can increase lung cancer risk by 62 times in non-smokers.
Smokers with this mutation are 25 times more likely to develop the disease.
Tobacco smoking, however, is still the leading cause of lung cancer. This unhealthy habit heightens lung cancer risk by four times in the general population.
Even so, this study further shows that smokers are not the only ones susceptible to lung cancer — which is the second most common cancer in the US. This dangerous disease is also the prime cause of cancer death in both men and women, according to the American Cancer Society.
Which mutation is increasing lung cancer risk?
As the study revealed, the T790M mutation in the epidermal growth factor receptor (EGFR) gene is strongly related to lung cancer risk.
EGFR is a protein that controls how cells grow and divide. When mutated, this protein can cause cancer cells to expand and spread.
Researchers studied 23andMe genotyping data across 3.37 million people and found the mutation to be prevalent in one in 15,850 individuals. Though 17 cancers and non-pulmonary conditions were evaluated, the T790M mutation only exhibited a significant association with lung cancer.
The T790M mutation originated in Southern Appalachian populations in the US about 200 to 225 years ago, according to the study.
EGFR mutation-positive lung cancer accounts for around 10-15% of lung cancers in the US, with an increased occurrence in Asian populations, according to the American Lung Association.
How can lung cancer screening help?
As with any cancer, screening and early detection for lung cancer can reduce the risk of death and increase life expectancy
“At the moment, screening for lung cancer is based, essentially, solely on tobacco exposure,” Pasi Jänne, M.D., Ph.D., a lung cancer specialist at Dana-Farber Cancer Institute and corresponding author, told Fierce Biotech.
“Here we’ve identified a genetic component that is also a risk factor, and maybe these are individuals that would benefit from screening and early detection to identify cancers at an earlier early [sic] stage when they’re still potentially curable.”
Jänne also pointed out that the study does not paint the entire picture regarding the lifetime risk of developing lung cancer in people who have the T790M mutation. Environmental factors may also play a role.
“There may be more nuances to the genetics of those individuals that modify the risk,” he added.
“Even in the presence of this mutation or environmental exposures that modify the risk.”
Scientists have developed different therapies used to go after EGFR-mutated lung cancer, including AstraZeneca’s Tagrisso and Johnson & Johnson’s Rybrevant.
Additionally, in August, BlossomHill announced a macrocyclic molecule that targets EGFR, called BH-30643, to compete with Tagrisso.
