What you need to know about lung cancer

Lung cancer is becoming increasingly more common. According to the American Lung Association, every 2 and a half minutes, someone is diagnosed with lung cancer in the U.S. While it is the top cause of cancer deaths, lung cancer is survivable — if caught early enough and treated. In fact, the survival rate for lung cancer increased 21% over the last 5 years.¹

Despite those advances, though, lung cancer is still the leading cause of cancer deaths in the United States, says Chinh Phan, D.O., medical director of interventional pulmonary services at UC Davis Health in California.

Many adults are not fully aware of the danger lung cancer may pose. A 2022 survey from the American Lung Association found that 73% of adults have not spoken with their doctor about their risk of lung cancer.²  While smoking is the leading cause of lung cancer, there are many other factors that can contribute to its development.

Here’s what you need to know about this serious disease.

Lung cancer — also known as carcinoma of the lung or pulmonary carcinoma — is a cancer that starts in the lungs and may spread to different parts of the body, including lymph nodes and other organs.³

Like other cancers, lung cancer occurs when there is cell growth that’s out of control. When we’re healthy, our body’s cells are in a constant state of regeneration: Our cells grow and multiply, and when they become old or damaged, they die. Then new ones take their place. With cancer, that process doesn’t happen as it should. Instead, abnormal or damaged cells grow and multiply, and those cells can form tumors, which in turn can spread and attack healthy cells and tissue. When that process starts in the lungs, it’s called lung cancer.^{3, 4}

Lung cancer isn’t just one disease — it’s an umbrella term for different types of cancers that start in the lungs. Lung cancers are typically divided into 2 categories, small cell lung cancer (SCLC) and non–small cell lung cancer (NSCLC).

• Small cell lung cancers are less common (about 10% to 15% of all lung cancers),⁵ but they are more serious. SCLCs tend to grow and spread more quickly than NSCLCs. In most people with SCLC, the cancer will have already spread to other areas of the body by the time it’s diagnosed.⁶
• Non–small cell lung cancers are more common and more likely to be treatable. The most common types of NSCLC include:⁷
  • Adenocarcinoma: The most common type of lung cancer, adenocarcinoma starts in the mucus glands. While there’s a strong correlation between this cancer and a history of smoking, it’s also the most common type of lung cancer to be found in people who’ve never smoked.³
  • Squamous cell carcinoma: This type originates in the cells that line the lungs’ airways.
  • Large cell carcinoma: This type can develop anywhere in the lungs.

It will come as no surprise that smoking is by far the number 1 risk factor for developing lung cancer. In fact, according to the American Lung Association, active smoking is the cause of nearly 90% of cases.⁸ However, lung cancer can also occur in people who have never smoked, according to the American Cancer Society.⁹

Breathing in radon — a colorless, odorless gas — is the second leading cause of lung cancer.^10,11 Radon is naturally found in soil, rocks and water. It can seep into your home, without you knowing it, through cracks and holes in the foundation.^10,11

Other risk factors for lung cancer include:

“Occupational and environmental carcinogens increase the risk of lung cancer,” says Nagendra Madisi, M.D., director of interventional pulmonology at Albany Medical Center in New York.

Exposure to the following chemicals can increase your risk for lung cancer:¹²

• Arsenic
• Asbestos
• Cadmium
• Chromium
• Coal Products
• Nickel
• Thorium
• Uranium
• Vinyl chloride

People who are exposed to secondhand smoke have a 20% to 30% increased risk of lung cancer, according to the Centers for Disease Control and Prevention.¹³

Radiation therapy in the chest area for cancer increases the risk of lung cancer.^10,11

Burning natural fuel, such as wood, kerosene, coal and charcoal for cooking or heating increases lung cancer risk.¹⁴

Studies have linked air pollution in the form of tiny little airborne particles from sources such as transportation, power generation and forest fire smoke to lung cancer.¹⁵

Constant exposure to vehicle exhaust puts people in professions such as truck driving at a higher risk of lung cancer.¹⁶

Having a parent who developed lung cancer may also increase your risk.¹⁷ “Lung cancer has a genetic component due to mutations in certain genes that lead to the production of specific proteins that cause tumor expression,” says Dr. Phan.

A cough that doesn’t go away, persistent chest pain and shortness of breath are all potential signs of lung cancer. If you are experiencing any of these symptoms, it’s important to see your doctor.¹⁸

To diagnose lung cancer, your doctor may ask about your medical history, order imaging tests to take a look at your lungs, or recommend a procedure such as a biopsy.¹⁹

Like most forms of cancer, the sooner lung cancer is detected, the better. “Treatment options for lung cancer are most effective if lung cancer is diagnosed earlier,” says Dr. Phan. For patients in the earlier stages, surgery to remove the cancerous tissue is often the best option.²⁰ This may be followed or complemented by radiation therapy to kill cancerous cells.²¹

For patients in the later stages of the disease, chemotherapy is often recommended. Chemotherapy medicines attack the cancer cells to kill or shrink them.²² Targeted therapy is another type of drug therapy that targets the proteins that cancer cells use to grow.²³

You can’t entirely prevent lung cancer, but there are important steps you can take to minimize your risk. For those who smoke, it's important to stop. “Quitting smoking is the most important thing a person can do to prevent lung cancer,” says Dr. Phan. You can also aim to reduce your risk of other hazards by using protective gear at work and checking for radon or asbestos in your home, for example.²⁴ If your doctor determines that you are at a high risk for lung cancer, frequent screenings are recommended.²