Nonsmokers also at risk for lung cancer

One common response to learning that an acquaintance has been diagnosed with lung cancer might be, “I didn’t know he smoked, or used to smoke.”

But the truth is that many cases of lung cancer are not related to tobacco. In fact, about 10% to 20% of Americans diagnosed with lung cancer have never smoked, according to the Centers for Disease Control and Prevention (CDC). “Never smokers” are individuals who have never smoked, or who have smoked less than 100 cigarettes during their life, according to the CDC.

While the rate of lung cancer diagnoses and death are declining — thanks to a decrease in the number of people who smoke and advances in screening and treatment –— the percentage of lung cancer cases among “never smokers” are rising accordingly. In fact, some studies say that not only is the proportion of lung cancer cases and never smokers rising, the actual number of cases also may be rising.


“The total incidence of lung cancer has declined significantly over the last few decades, in part because we now have 10% to 15% of the population smoking, as opposed to roughly half the adult population in the 1960s,” said Ian Horkheimer, MD, a board-certified medical oncologist and hematologist who practices in the Little Silver office of Regional Cancer Care Associates LLC, one of the nation’s largest networks of cancer specialists.

Beyond the statistics, Dr. Horkheimer said, lung cancer in never smokers is a significant concern: Up to 20% of people who die from lung cancer never smoked.

Lung Cancer Risk Factors in Never Smokers

The reason nonsmokers develop lung cancer has yet to be determined. However, there are several risk factors that everyone should be aware of, including:

Another area of concern is family history, and some studies indicate that the human papillomavirus (HPV) may be a risk factor, but other studies have been unable to find a link. However, both potential risk factors need further study to see if there is a connection.

Dr. Horkheimer said he is particularly concerned about vaping and electronic cigarettes, which deliver concentrated nicotine and other carcinogens to varying degrees.

“Vaping is a relatively young habit within the last decade or so, so we really haven’t seen the ramifications,” he said. “I’ll be surprised if there is not an increased incidence of cancer in e-cigarette users, but time will tell. We won’t know the real cancer risk for another 20 or 30 years for youngsters who started out vaping instead of smoking cigarettes. And then there are the older folks who for some reason thought they would quit smoking and go on to vaping. The effect on them will be difficult to tease out.”

Another risk factor is sex. Dr. Horkheimer noted that lung cancer is more common in female nonsmokers than in male nonsmokers, adding that male nonsmokers are more likely to die of the disease.

Lung Cancer Symptoms

While nonsmokers have the same symptoms as those who do smoke, nonsmokers are more likely to dismiss them, chalking them up to something else rather than seeking medical attention, giving the disease more time to spread.

“Someone who otherwise feels absolutely fine might ignore a little cough, thinking it may be something like allergies. They may not see their doctor about it as soon as they should,” said James Lee, MD, a board-certified oncologist in RCCA’s Moorestown office.

Dr. Horkheimer agreed. “I tell people that if they have a symptom that comes and then goes away, cancer doesn’t do that. If you have a new symptom and it comes and doesn’t go away, and continues to get worse, seek medical attention sooner rather than later. If you have a problem for a couple of weeks, it needs to be evaluated,” he said.

Individuals should see a doctor if they persistently experience any of the following symptoms:

Types of Lung Cancer

Those with lung cancer are diagnosed with one of two forms: non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC). The two types develop differently. Most nonsmokers, light smokers and former smokers develop a subtype of NSCLC called adenocarcinoma.

Because of biological differences between some tumors in nonsmokers and current or former smokers, many experts believe that some non-small cell lung cancers in never smokers could represent a different disease than NSCLC in smokers. That’s because tobacco damages the DNA in smokers’ cells, while a genetic mutation is responsible for the damage to the cells of many never smokers.

Age also may be a factor. A 2019 review of data from previously published studies found that, relative to current or former smokers, never smokers who developed lung cancer are younger, have more favorable outcomes and respond better to treatment.

Treatment Options

Lung cancer treatments for never smokers and smokers are the same, and include one or one or more of the following:

The five-year relative survival rate for people with NSCLC ranges from 63% for early-stage lung cancer that hasn’t spread beyond the lung to 7% for cancer that has spread to other parts of the body, such as the brain, bones, liver or other lung, according to the American Cancer Society.

“As we learn more about what causes these cancers, we’re learning more about their molecular biology,” Dr. Lee said. “We have already identified at least a half-dozen mutations and we have drugs for them. Lung cancer is becoming a more treatable illness. It’s a rapidly advancing field, and at RCCA we offer our patients the latest evidence-based therapies for lung cancer, as well as access to clinical trials.”

Protecting Your Respiratory Health

In addition to doing the obvious and not smoking, other steps to increase respiratory health include:

Drs. Horkheimer and Lee are among the more than 80 cancer specialists who treat patients at 20-plus RCCA care centers in New Jersey, Connecticut, Maryland and the Washington, D.C., area. These oncology specialists see more than 22,000 new patients each year and provide care to more than 225,000 established patients, collaborating closely with their patients’ other physicians. They offer patients the latest in cutting-edge treatments, including immunotherapies and targeted therapy, as well as access to a wide range of clinical trials. In addition to serving patients who have solid tumors, blood-based cancers and benign blood disorders such as anemia, RCCA care centers also provide infusion services to people with a number of non-oncologic conditions — including multiple sclerosis, Crohn’s disease, asthma and rheumatoid arthritis — who take intravenously-administered medications.


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Regional Cancer Care Associates is one of fewer than 200 medical practices in the country selected to participate in the Oncology Care Model (OCM); a recent Medicare initiative aimed at improving care coordination and access to and quality of care for Medicare beneficiaries undergoing chemotherapy treatment.