Radon, secondhand smoke, air pollution, workplace exposures and genetic changes may increase risk.
Routine screening is not currently recommended for people without a significant smoking history.
Persistent or unexplained symptoms should be evaluated by a healthcare provider.
Can you get lung cancer if you have never smoked?
Yes. About 15% to 20% of lung cancers in the United States occur in people who never smoked or smoked fewer than 100 cigarettes in their lifetime. Risk factors can include radon, secondhand smoke, air pollution, workplace exposures and genetic changes.
Cancer care built around your life
At Winship, physicians and care teams bring together specialized expertise and advanced treatment options to develop a personalized plan for your cancer. If you've been diagnosed with cancer or want a second opinion, we’re here for you. Request an appointment.
A routine CT scan leads to an unexpected diagnosis
Lung cancer was the last thing on Mary's mind when she underwent a CT scan before a cardiac ablation procedure to treat atrial fibrillation.
A 73-year-old retired nurse and lifelong nonsmoker, Mary had no cough, shortness of breath or other symptoms.
But the scan revealed a tiny 6-millimeter nodule in her right lung. Over the next several months it kept growing.
As a result, Mary met with Emory thoracic surgeon Rachel Medbery, MD. Because the nodule had changed over time, Dr. Medbery recommended surgery rather than continued monitoring. It was the right call. When the lesion was removed, the diagnosis was adenocarcinoma, one of the most common types of lung cancer.
Fortunately, the cancer was caught early and removed with surgery before it spread to nearby lymph nodes, so Mary did not need chemotherapy or radiation.
"I thought, ‘I'm not a smoker, so it isn't going to happen to me,’" she says. "But it sure can."
Mary’s experience highlights an important reality: an increasing number of people diagnosed with lung cancer have little or no history of smoking.
How common is lung cancer in people who have never smoked?
"Contrary to popular belief, lung cancer is not exclusively a smoker's disease," says Dr. Carlisle.
Why? Part of the answer is actually good news. Smoking rates have declined significantly over the past several decades, so lung cancers diagnosed in people who never smoked now make up a larger share of cases.
"Lung cancer in nonsmokers has increased from about 10% to 15% in the 1990s to roughly 20% today," says Dr. Carlisle.
What causes lung cancer in nonsmokers?
Smoking-related lung cancer usually develops after years of repeated damage to lung cells from tobacco smoke.
In many people who have never smoked, lung cancer may be driven by changes in genes that cause cells to grow abnormally. Researchers are still studying why these changes occur.
Environmental and workplace exposures that can increase lung cancer risk include:
Secondhand smoke
Air pollution and exposure to fine particulate matter
Radon gas
Occupational exposures such as asbestos and heavy metals
"Most people's houses get checked for radon when they're bought or sold, but radon levels can change over time."
Jennifer Carlisle, MD, thoracic medical oncologist
Don't overlook radon
Radon is a naturally occurring radioactive gas that can enter homes through cracks in foundations and accumulate indoors.
Dr. Carlisle says it's a particularly important risk factor for Georgia residents to be aware of.
"Most people's houses get checked for radon when they're bought or sold, but radon levels can change over time," she says.
Home radon test kits are widely available, and professional mitigation systems can reduce exposure if elevated levels are detected.
Are some people at higher risk?
Lung cancer in nonsmokers is more common in women and in people of Asian ancestry. Compared with smoking-related lung cancer, lung cancer in never-smokers is often diagnosed at younger ages.
Most cases of lung cancer in nonsmokers are a subtype called adenocarcinoma, a form of non-small cell lung cancer. This was the type of cancer diagnosed in Mary after surgeons removed the nodule found in her right lung.
Researchers have identified several genetic mutations that commonly drive these cancers. Understanding these mutations has helped physicians develop targeted treatments tailored to specific tumors.
"Unless something is causing major airway blockages or bleeding, we just don't feel lung cancer growing."
Jennifer Carlisle, MD, thoracic medical oncologist
What symptoms should you watch for?
One of the biggest challenges with lung cancer is that symptoms often don't appear until the disease is more advanced.
"Unless something is causing major airway blockages or bleeding, we just don't feel lung cancer growing," says Dr. Carlisle.
Symptoms can include:
Persistent cough
Shortness of breath
Unexplained weight loss
Fatigue
Chest pain
Recurrent respiratory infections
Coughing up blood
Not everyone experiences symptoms, however. Mary never had a cough, shortness of breath or other warning signs. Her cancer was discovered incidentally during imaging performed for an unrelated heart condition.
Because lung cancer is less common in nonsmokers, symptoms are often attributed to conditions such as pneumonia. Dr. Carlisle says patients and clinicians should ensure follow-up imaging confirms that the pneumonia is resolving as expected.
"The cure rate for stage 1 lung cancer is much higher than stage 3 lung cancer."
Jennifer Carlisle, MD, thoracic medical oncologist
Why does early detection matter?
Finding lung cancer earlier, before it has spread, can improve treatment options and outcomes.
"The chance of successful treatment for stage 1 lung cancer is much higher than stage 3 lung cancer," she says.
For Mary, early detection made all the difference. Her cancer was discovered before it caused symptoms, and surgeons were able to remove it with clear margins before it spread to her lymph nodes. She did not require additional cancer treatment after surgery.
"I feel very fortunate," she says.
How is treatment improving?
Lung cancer treatment has changed dramatically in recent years.
At Winship Cancer Institute’s lung cancer program, doctors look for specific genetic changes in a patient's tumor to help determine the best treatment. Some patients may benefit from targeted therapies that are designed to attack cancers with certain mutations. Others may be candidates for immunotherapy, which helps the body's immune system fight cancer.
"We've identified new targetable mutations and new therapies at a remarkable pace," says Dr. Carlisle.
Because new treatments and clinical trials are constantly emerging, Dr. Carlisle says it can be valuable to work with specialists who focus solely on lung cancer. At Winship, medical oncologists, thoracic surgeons and radiation oncologists work together to develop personalized treatment plans for each patient. Researchers also continue to lead clinical trials aimed at improving treatment options and outcomes.
"I'm not a smoker, and I never expected to hear the words 'lung cancer.' If something doesn't seem right, get it checked out. And remember, lung cancer can happen to people who never smoked."
Mary, nonsmoking lung cancer patient
When should you talk with a doctor?
Routine lung cancer screening is not currently recommended for people without a significant smoking history.
Never smoked but experiencing symptoms?
If you have a persistent cough, shortness of breath, chest pain, coughing up blood, unexplained weight loss or other concerning symptoms, schedule an appointment with your primary care provider. These symptoms can have many causes, and your doctor can help determine whether further evaluation is needed.
Have a history of smoking?
If you’re age 50 to 80 with at least a 20 pack-year smoking history and currently smoke or quit within the past 15 years, you may qualify for annual lung cancer screening. Talk with your doctor about whether screening is right for you or learn more about Emory Healthcare’s Lung Screening and Nodule Program.
Have you been diagnosed with lung cancer?
If you have been diagnosed with lung cancer or would like a second opinion, connect with the lung cancer specialists at Winship Cancer Institute of Emory University.
A chest X-ray revealed Natalie had a rare cancer. When standard treatments failed, a clinical trial at Winship at Emory had positive outcomes.
In observance of World Cancer Day, here are three inspiring stories of cancer survivors treated at Winship Cancer Institute of Emory University.
A 39-year-old mother was devastated to learn she had stage three lung cancer. All she could think about were her four children.