Lung cancer not always linked to smoking, especially in women

Published 2:30 pm Saturday, August 27, 2022

Many people think that lung cancer only affects smokers, but doctors say evidence shows that isn’t always the case, especially in women.

According to Dr. Nitika Sharma, of Cancer Treatment Centers of America, about half of women worldwide who develop lung cancer never smoked compared to the 15 to 20 percent of male nonsmokers who develop lung cancer. The difference isn’t quite so drastic in the United States. Twenty percent of women with lung cancer are nonsmokers and about 10 percent of men are non-smokers in the U.S.

“A lot of times, smoking is kind of associated with stigma and people think that you did this to yourself,” Dr. Sharma said.

But more and more oncologists are realizing that, while smoking history is important to know, other factors also cause the disease.

“Lung cancer is not just one disease these days,” Sharma said. “Lung cancer is a more genetically diverse disease than what we previously thought.”

Depending on someone’s smoking status, doctors will take different approaches to identifying the type of cancer. If a young nonsmoker presents cancer symptoms, oncologists might look for one set of mutations, but look for different mutations that could be driving a cancer in smokers.

Apart from smoking, other causes of lung cancer include: hereditary risk factors, radon exposure, asbestos exposure, air pollution and secondhand smoke.

Because of this, doctors recommend staying on top of lung health, even if one has never smoked.

“It’s important to look for symptoms, including cough, shortness of breath, chest pain, productive sputum, blood in the sputum, any other common symptoms that are unusual for individuals, such as bone pain, unusual headaches, weight loss, loss of appetite,” Sharma noted.

This isn’t an exhaustive list, she said, but these symptoms should always be evaluated.

Dr. Sharma touted the importance of getting screened for cancer in high-risk individuals. Last year, the U.S. Preventive Services Task Force (USPSTF) reduced the recommended age of screening from 55 to 50.

Anyone 50 years or older, who has at least a 20 pack-year history of smoking in their lifetime, and is an active smoker or has quit within the last 15 years, qualifies for lung cancer screening.

Pack-years are a method of measuring how much a person has smoked over time. If a person smoked a pack per day for the last 20 years, or two packs per day for the last 10 years, they have 20 pack-years.

With the new guidelines, an estimated 6.5 million more Americans will be eligible for screening, which could save upwards of 80,000 lives per year, according to Sharma.

With the changes that were made in 2021, doctors are really looking to include more at-risk women and racial minorities in screenings.

“African Americans and women tend to see greater impacts of tobacco use with lesser exposure. They may not have smoked for that long, but still had greater impact from those risk factors,” Dr. Sharma said.

“Smoking is a very preventable risk factor for lung cancer, but I think this stigma of lung cancer is always associated with smoking,” Sharma said.

“Now, we have evidence that really anybody who has lungs can develop lung cancer. The important thing is to look for signs or symptoms and to get them evaluated promptly.”

Sharma is a medical oncologist and hematologist at Cancer Treatment Centers of America, Atlanta.