Understanding the Risk for Lung Cancer in Non-Smokers
If you have never smoked, or quit years ago, you may think your chances of developing lung cancer are slim to none. While it’s true that each year spent tobacco-free decreases your risk, there are still other significant risk factors that everyone should be aware of. Exposure to secondhand smoke, specifically, makes lung cancer in non-smokers much more common than you may think.
According to the American Cancer Society, approximately 228,000 new cases of lung cancer will be diagnosed in the U.S. this year alone, and of those, nearly 23,000 (10-15 percent) cases will occur in non-smokers. If you were to consider lung cancer in non-smokers as a separate concern, it would rank as the sixth deadliest cancer.
While it’s not yet evident if there has been an increase in lung cancer cases among non-smokers in the U.S., more and more people are being diagnosed incidentally, when receiving CT scans for other reasons, explains Dr. Duane Monteith, thoracic surgeon and Medical Director of Thoracic Oncology at the Sidney Kimmel Cancer Center – Washington Township.
It’s important to know that other known risk factors for lung cancer, aside from smoking, include exposure to secondhand smoke, radon, asbestos, and other carcinogens, and air pollutants, such as arsenic and diesel exhaust. Women non-smokers of Asian descent have also been shown to be at an increased risk for non-small cell lung cancer (the most common lung cancer type), which has been linked to a specific genetic mutation.
Many studies show secondhand smoke actually has more dangerous toxins than what the actual smoker inhales, says Dr. Monteith. Secondhand smoke contains more than 7,000 chemicals, at least 70 of which can cause cancer, states the CDC.
“For family members of smokers, this is incredibly dangerous,” said Dr. Monteith. “It’s nearly impossible for them to avoid exposure, and many other health complications can arise.”
CDC data shows that secondhand smoke exposure increases the risk for lung cancer by 20-30 percent, cardiovascular disease by nearly 30 percent, and stroke by 20-30 percent. Secondhand smoke may cause children to be more susceptible to underdeveloped lungs, asthma, bronchitis, pneumonia, and even SIDS (sudden infant death syndrome).
Lung cancer presents similarly – with few or no early warning signs – in smokers and non-smokers. Generally, those who present with symptoms are suffering from a cancer of a more advanced stage. These symptoms may include chronic or worsening cough, coughing up blood, and/or frequent lung infections.
Unfortunately, outcomes for non-smokers tend to be worse. This is because the cancer is often diagnosed at a much later stage, as that person was never considered at-risk, explains Dr. Monteith. Non-smokers have virtually no access to lung cancer screening (detection through low-dose CT scans), as the current guidelines place a heavy focus on smoking history.
“Lung cancer screening, in comparison to mammograms and colonoscopies, is a relatively new concept,” explained Dr. Monteith. “The U.S. Preventive Services Task Force only just accepted the method in 2013; the CMS (Centers for Medicare and Medicaid Services), in 2015. With new research constantly emerging, screening guidelines are being analyzed in hopes to break down these barriers to early detection.”
If you have had significant exposure to secondhand smoke or other carcinogens, and are experiencing respiratory issues, Dr. Monteith continues, your primary care physician may refer you to have a CT scan, based on the symptoms.
Ultimately, as a non-smoker, the primary way to decrease your risk for lung cancer is to avoid or eliminate this exposure as much as possible. If exposure is occupational-related, be sure to always wear the proper protective gear!