Danger in the Air: How to Protect Yourself from Lung Cancer

Lung Cancer and Nonsmokers: Know Your Risk

Kathy O'Brien of Westfield, New Jersey, thought her eyes were playing tricks on her. She was driving her three kids to school two years ago when she noticed that the stop sign was blurry. Her eye doctor sent her to a retina specialist, who spotted six tumors in her left eye and four in her right. The next day -- after a battery of tests including an MRI and a CT scan -- Kathy was in an oncologist's office, blindsided by news that was beyond shocking: She had stage IV lung cancer. "Never in a million years did I think I'd hear some­thing like that," says Kathy, who had recently run her fifth marathon and had become certified as a Bar Method exercise instructor. "It seemed impos­sible because I had never smoked."

Kathy, now 41, isn't the only fit woman facing such a diagnosis. One in five American women who contract lung cancer this year will be what researchers call "never smokers" -- those who have taken a drag on fewer than 100 cigarettes in their lives. Sixty percent of never smokers with lung cancer are women. In fact, the number of such women diagnosed each year in the United States -- roughly 20,000 -- is comparable to the number of women who are found to have ovarian cancer. And never-smokers' cancer can strike young. "In my practice, I've seen women in their twenties, thirties, and forties with the disease," says Christina Baik, MD, a thoracic oncologist and staff scientist at the Fred Hutchinson Cancer Research Center in Seattle.

The first question people ask Kathy when she says she has lung cancer is whether she smoked. "When I say no, I almost feel as if they don't believe me," she says.

Until about 10 years ago, even doctors found it improbable that nonsmokers could have lung cancer. "If a young woman came in with a spot in her lung, it was presumed to be cancer that spread from someplace else," says Joan Schiller, MD, the president of the National Lung Cancer Partnership. "Patients were being misdiagnosed."

During the last decade, though, scientists discovered that specific gene mutations were more commonly occurring in never smokers. This finding signaled that lung cancer wasn't a disease that affected everyone uniformly, and researchers began focusing on never smokers. Hollywood lifted the smokescreen for the rest of us in 2006 when Dana Reeve, the wife of the late actor Christopher Reeve, died of lung cancer at the age of 44 without ever having smoked a cigarette.

Doctors haven't pinpointed why nonsmokers get lung cancer. A lot of research is centered on the air we breathe: Secondhand smoke contributes to more than 3,000 lung cancer deaths among nonsmokers every year, according to the National Cancer Institute. Three thousand more nonsmokers with lung cancer die annually after being exposed to radon; this odorless, invisible radio­active gas comes from the natural breakdown of uranium in soil, rock, and water and seeps into homes through cracks and holes in the foundation. Pollution is another potential culprit. University of Ottawa researchers recently found that people who have never smoked, but who live in areas with high air-pollution levels, are roughly 20 per­cent more likely to die from lung cancer than people who live in areas with cleaner air.

Your sensitivity to harmful particles in the air may be a trait that runs in your family. When you breathe in carcinogens, they are absorbed into the bloodstream, and it's your liver that's in charge of clearing them out. The latest research suggests that some people may have livers that are sluggish, allowing carcinogens to linger in the bloodstream and do their damage; others, Dr. Schiller explains, may have the type of overactive livers that break down nonharmful molecules and turn them into carcinogens. These molecules are then sent back into the blood to circulate throughout the body; if lung cells absorb them, that is where the cancer will grow.

Science hasn't given Emily Roberts, 38, of Tustin, California, any insight into the cause of what tests revealed to be a baseball-size tumor in the lower part of her left lung three years ago. A vegetarian and an avid hiker, she had always been the one in her family with an immune system of steel, staying healthy even when her husband or three boys picked up colds or the flu. But after she suddenly blacked out one night, an MRI revealed lesions on her brain, and further tests showed they had spread from her lung. "I have no significant risk factors for lung cancer, like smoking, radon exposure, or living in an area with air pollution," Emily says. "It just happened."

Perhaps Emily's greatest risk factor is that she's a woman. Never-smoking women are almost twice as likely to be diagnosed with lung cancer as never-smoking men. Researchers suspect that hormones may play a role. In a study of more than 100,000 women, Dr. Baik found that the more children a never-smoking woman had, the less likely she was to get lung cancer. "It's possible that pregnancy may change a woman's lung cells, making them resistant to cancer," she says.