Lung Cancer in Never Smokers

Cancer November 27, 2019
lungs nonsmokers

While about 80% of lung cancer deaths are related to cigarette smoking, lung cancer is not always “a smoker’s disease.” In fact, more and more people who have never picked up a cigarette, or have smoked fewer than 100 cigarettes in their lifetime, are being diagnosed with lung cancer. The growing phenomenon has been coined “LCINS” — or lung cancer in never smokers. 

The stats you may not know

  • Lung cancer is the leading cancer killer of both men and women in the United States, causing more deaths each year than colon, breast and prostate cancers combined. 
  • If the disease in never smokers had its own separate category, it would rank among the top 10 most fatal cancers in the United States. 
  • Never smokers make up 10% to 20% of all people in the U.S. diagnosed with lung cancer. 
  • For men it’s 10%, but for women it can be as high as 20%. 
  • A growing number of these patients are often under 55 years old, and LCINS is frequently diagnosed at a later stage, when it is less curable.

Risk factors beyond smoking

Lung cancer develops when cells in the lung mutate or change. Smoking tobacco has been shown to directly cause lung cancer, but for never smokers, it is difficult to determine a single factor that is directly responsible for the disease.

When patients present with respiratory symptoms and they’ve never smoked, lung cancer is not the first diagnosis that physicians think about.

While researchers are making progress in understanding risk factors for never smokers, a lot is still unknown. Some risk factors for lung cancer in never smokers include second-hand smoke, along with environmental and occupational exposures. This includes exposure to radon, asbestos and other indoor and outdoor air pollutants and substances that could be inhaled.

A difficult disease to diagnose

The lack of awareness about the risk factors other than smoking can make diagnosing lung cancer in never smokers a challenge. 

“When patients present with respiratory symptoms and they’ve never smoked, lung cancer is not the first diagnosis that physicians think about,” says Marta Batus, MD, a medical oncologist at Rush who specializes in lung cancer. “Some patients find out they have lung cancer incidentally after having a workup for another condition or symptom.”

Lung cancer symptoms include the following:

  • Persistent cough
  • Coughing up blood
  • Unexplained weight loss
  • Shortness of breath
  • Fatigue

However, these subtle symptoms are also common in a variety of other, less serious conditions. That’s why it's important to be aware of changes to your health, and to follow up with a doctor if you have any symptoms that are persistent and not going away on their own.

The smoker stigma

Lung cancer is still seen as “the smoker’s disease,” despite the growing number of never smokers who are affected each year. Upon telling people about their lung cancer diagnosis, never smokers often feel the need to follow it with an “I’ve never smoked” explanation to avoid the stigma that accompanies the condition. 

Batus is hopeful that in the next few years researchers will uncover more information about what is causing LCINS, which can help continue to raise awareness and, ultimately, lead to novel ways to diagnose lung cancer earlier in never smokers.

“I think in recent years things have changed for better for the patients because of social media and support groups, so I think people are seeing lung cancer as a different disease these days,” Batus says. “We need to continue raising awareness as well as getting these patients together and providing them the support that they need from their first visit.”

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