Smoking is far and away the No. 1 cause of lung cancer, according to the Centers for Disease Control and Prevention (CDC), accounting for 80 to 90 percent of all cases.
But while most people have long understood this link between smoking and lung cancer, you might be surprised to learn that the number of never-smokers diagnosed with lung cancer is on the rise. In fact, 20 percent of people who die from lung cancer have never smoked, according to the American Cancer Society (ACS).
What’s more, lung cancer in never-smokers seems to be affecting a younger population.
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“Lung cancer seems to be increasing in young people in their thirties and forties who have never smoked a day in their life,” says Michael Wert, MD, a pulmonary disease and critical care medicine doctor with the Ohio State University Wexner Medical Center in Columbus.
Experts are still trying to figure out exactly why that is, but both the CDC and ACS note that other potential causes include high levels of radon in homes (which can go easily undetected), exposure to secondhand smoke, and family history.
The ACS points out that heavy air pollution, as well as carcinogens like asbestos, may also be to blame.
The trend has been on the rise for some time. In fact, the proportion of patients who’ve never smoked that are diagnosed with non-small-cell lung cancer (the most common type of lung cancer) rose from 8 percent from 1990 to 1995 to 14.9 percent from 2011 to 2013, according to a study from 2017.
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Screening Is Not an Option for Nonsmokers
Unfortunately there’s no easy way to identify the disease in nonsmokers. Doctors can screen for lung cancer with a low-dose computed tomography (LDCT) scan. But screening is reserved for people known to be at high risk.
Currently, people who are eligible for lung cancer screening are ages 55 to 80 and are active smokers or have quit within the last 15 years, says Dr. Wert. They also need to have smoked one pack per day for 30 years or two packs per day for 15 years.
Few people at high risk seem to take advantage of screening. “Recent estimates suggest less than 5 percent of eligible patients get them,” says Dr. Wert, and as was noted in a 2019 report.
Without screening, it’s tough to catch lung cancer at an early stage. By the time most people experience symptoms concerning enough to warrant a call to their doctor, the cancer may be advanced.
Can You Spot Early Symptoms of Lung Cancer?
Given the rise in lung cancer in people who don’t appear to have risk factors for the disease, it’s important to pay attention to troubling symptoms and bring them to a doctor’s attention.
Here are five early warning signs to be attuned to, according to Wert.
Shortness of Breath Shortness of breath is one of the main symptoms of COVID-19 and other respiratory viruses. But it’s also a symptom of lung cancer. If you’re an active person who can no longer walk up a few flights of stairs without stopping to huff and puff, then this is an unusual and concerning symptom.
Racing Heart “The younger people we end up diagnosing tend to have been active people,” says Wert. They’re the type to go on a five-mile run, and now they can feel their heart beating out of their chest as they walk to their car in the parking lot, he says. “Heart racing with minimal activity can be the first warning sign that something is going on,” he says.
Chronic Cough Catching a cold or the flu virus is common, especially in the winter. And coughs can linger for a longer time than you’d expect (on average for 18 days). A dry, persistent, nagging cough that’s been around for four to six weeks or longer, however, may be an indication that you need an X-ray to check on your lungs.
Coughing Up Blood “This is never normal, and it requires an urgent evaluation,” says Wert. The causes can range from lung cancer to bronchitis or a viral or bacterial infection.
Weight Loss, Fever, Night Sweats Weight loss without dieting, fevers not related to an illness, or profuse night sweats “are all symptoms that would prompt your doctor to evaluate you for a hidden cancer,” says Wert.