Understanding Lung Cancer: It's Not Just One Disease but Many

For years, lung cancer has carried a stigma that many other cancers do not. Too often, the first question people ask is whether the patient smoked.

Bruna Pellini, M.D., thoracic oncologist and chief of thoracic oncology at Baptist Health Herbert Wertheim Cancer Institute, says that question misses a much larger truth.

“If you have lungs, you can have lung cancer,” Dr. Pellini says.

The American Cancer Society estimates that 229,410 new lung cancer cases will be diagnosed in the U.S. in 2026, of which 124,990 will prove fatal. It describes lung cancer as “the second most common cancer in men and women,” excluding skin cancer, and “by far the leading cause of U.S. cancer death.”

Smoking and Other Risk Factors

Smoking remains the leading risk factor for lung cancer but some people diagnosed with the disease have never smoked at all. Other factors can also play a role, including secondhand smoke, radon exposure, air pollution, diesel exhaust, asbestos, arsenic, certain workplace chemicals and family history.

That’s why Dr. Pellini believes it is important to move away from blame and toward awareness. Lung cancer is common, serious and often deadly — but it is also a disease where medicine has made remarkable progress.

“It is an amazing time to be a lung cancer oncologist,” she says.

Anyone With Lungs Can Be at Risk

Part of the challenge with lung cancer is that symptoms often do not appear until the disease has already advanced.

That makes awareness especially important. A persistent cough, coughing up blood, chest pain, shortness of breath, unexplained weight loss, fatigue or recurring respiratory infections should be discussed with a healthcare provider.

But Dr. Pellini emphasizes that risk is not limited to one kind of person. The old image of lung cancer as only a smoker’s disease can prevent people from recognizing symptoms, asking questions or seeking care. It can also make patients feel judged at the very moment they need support.

The more accurate message, she says, is simple: anyone with lungs can develop lung cancer.

The Screening Gap

One of the most powerful tools for improving lung cancer outcomes already exists: screening.

Low-dose CT screening can detect lung cancer earlier, when it is more likely to be treated successfully. Yet too few eligible people take advantage of it. According to Dr. Pellini, fewer than one in five eligible patients undergo lung cancer screening — an improvement from about 6 percent a decade ago, but still far too low.

Screening criteria from the United States Preventive Services Taskforce (USPSTF) generally apply to adults ages 50 to 80 who have at least a 20-pack-year smoking history and currently smoke or quit within the past 15 years. A pack-year is calculated by multiplying the number of packs smoked per day by the number of years a person smoked.

Dr. Pellini says those guidelines save lives, but they’re also imperfect. She has seen patients develop lung cancer even though they didn’t meet the current screening criteria. That is one reason she believes lung cancer awareness must continue to grow.

She also stresses that a chest X-ray is not an adequate screening test for lung cancer. A thorough screening requires a low-dose CT scan, which is more sensitive and better able to find small, early lung cancers.

For those who are eligible, the message is clear: do not wait. Ask your physician whether lung cancer screening is right for you.

Not One Disease, But Many

Another major shift in lung cancer care is the understanding that lung cancer isn’t simply one single disease.

“It’s not enough to say, ‘I have lung cancer,’” Dr. Pellini explains. Doctors need to know what kind.

The first major distinction is usually between non-small cell lung cancer and small cell lung cancer. Non-small cell lung cancer is the most common category, accounting for more than 80 percent of all cases. It includes subtypes such as adenocarcinoma, squamous cell carcinoma and large cell carcinoma.

Small cell lung cancer, which accounts for about 10 to 15 percent of cases, tends to be more aggressive and may initially respond well to treatment, though it often requires a different treatment approach than non-small lung cell cancer, Dr. Pellini notes.

But today, the classification goes much deeper. Doctors now look for biomarkers, gene alterations and protein markers that help define each patient’s cancer more precisely. These details can influence which treatments are most likely to work.

That is why biopsy tissue is so important, says Dr. Pellini. “A small sample may confirm cancer, but doctors often need enough tissue to run comprehensive testing. If the sample is too limited, a repeat biopsy may be necessary — which can be frustrating for patients, but sometimes essential.

The goal, Dr. Pellini says, is not to start just any treatment. It is to choose the best treatment from the very beginning.

Genetic Testing Is Changing Treatment

“Comprehensive genomic testing, also called next-generation sequencing, has transformed lung cancer care,” Dr. Pellini says. “Instead of testing for only one mutation, doctors can examine many genes at once to look for cancer-driving changes.”

Those results can open the door to targeted therapies — drugs designed to attack specific alterations in cancer cells. For some patients, these treatments can control their disease for years.

Testing can also include protein markers that help determine whether immunotherapy may be effective. Immunotherapy helps the immune system recognize and attack cancer, and it has become an important treatment option for many patients, according to Dr. Pellini.

In some cases, doctors may also use a liquid biopsy, a blood test that looks for circulating tumor DNA. This can sometimes identify a targetable mutation faster than tissue testing, particularly in stage 4 disease.

“However, a negative liquid biopsy does not always mean there are no mutations; there may simply not be enough cancer DNA in the blood,” notes Dr. Pellini. “That is why tissue testing is critical.”

A More Personalized Future

Lung cancer remains a serious diagnosis, but it is no longer approached with a one-size-fits-all plan. Depending on the cancer’s stage, subtype and molecular profile, treatment may include surgery, radiation, chemotherapy, targeted therapy, immunotherapy or a combination of these.

For patients and families, Dr. Pellini encourages advocacy. “Ask what type of lung cancer it is. Ask whether biomarker testing has been done. Ask whether there is enough tissue for comprehensive testing. Ask about clinical trials,” Dr. Pellini advises.

Clinical trials, she says, are how today’s best treatments became available — and they may offer access to tomorrow’s best treatments today.

The progress in lung cancer care is real, Dr. Pellini emphasizes. “But so is the need for earlier detection, broader screening and less stigma,” she adds.

Click here for more information on lung cancer treatments and specialists available at Baptist Health Herbert Wertheim Cancer Institute.