Lung cancer

About one in 15 men and one in 17 women will get lung cancer, according to theAmerican Cancer Society (ACS). Lung cancer is the third most common cancer, afterskin cancer,prostate cancer(men) andbreast cancer(women).

Despite a decrease in cases due to less smoking, lung cancer remains the most common cause of death from cancer in both men and women. Smoking is most often the cause.

• About 237,000 cases of lung cancer are diagnosed every year—and smoking contributes to the cause in about 80 percent of these cases, according toACS.
• The risk increases with the number of years and the number of cigarettes you smoke. Cigar and pipe smoking poses only slightly less of a risk than cigarette smoking.
• Secondhand smokefrom tobacco is also a risk and may cause about 7,000 lung cancers each year.

Lung cancer typically develops in people older than 65. The average age of diagnosis for lung cancer is 70, with men at slightly higher risk than women.

Radon, a radioactive gas that leaks from soil and rock, is the second leading cause of lung cancer. It may be the leading cause for patients who never smoked tobacco. Radon is most dangerous in basements where it’s concentrated, not out in open air.

Other much-less common risk factors for lung cancer include:

• Exposure to asbestos
• Inhaled toxins from industrial chemicals or radioactive ores
• Radiation therapytreatments of the chest, as in treatments for breast cancer or Hodgkin lymphoma
• Airpollution
• Family historyof lung cancer, especially if diagnosed at a young age
• Smoking marijuana or e-cigarettes may pose a risk, although more research is needed

Learn about risk factors for lung cancer

The diagnostic process may begin with or without symptoms.

A lung cancer screening, which is testing before the appearance of symptoms, involves alow-dose computed tomography (CT) scan. Thistype of imaging study建议只对高危人群陆吗ng cancer.

According to theAmerican Lung Association, you may be screened if:

• You are 55 to 80 years old.
• You’ve smoked at least a pack of cigarettes per day for 30 years or an equivalent number, such as two packs per day for 15 years.
• You are still smoking or you quit within the past 15 years.

Diagnosing lung cancer typically starts with a history and physical exam. The next step may be an imaging study—such as achest X-ray,CT scanorPET (positron emission tomography) scan—to search for cancer in your lungs. Some patients may undergo a bone scan, an imaging study of the bones, to determine whether cancer has spread there.

Doctors use abiopsyto identify cancer cells, removing a piece of lung tissue or cells to study under a microscope. Common methods to obtain these samples include:

• Removing cells through a tube placed into the lung or lung passages
• Removing fluid or tissue from the lung using a needle
• Collecting sputum from the lung

Learn about diagnostic tests for lung cancer

As you learn more about your cancer and the available treatments, you’ll share in the decision-making process with your care team.

Treatments for NSCLC vary by stage and may include:

• Stage 0: This cancer hasn’t spread into lung tissue, so surgery is typically the sole treatment. In most cases, doctors may remove a wedge of lung tissue.
• Stage 1: Surgery may be the only treatment needed for this stage, although a larger section of lung may need to be removed. If there’s evidence of cancer near the edge of the removed lung or near alymph node, surgery may be followed bychemotherapy(cancer drugs) orradiation therapy(ionizing radiation treatments).
• Stage 2: You may need surgery to remove a whole lobe of lung or the entire lung. Chemotherapy often follows surgery. If tests certain DNA changes (mutations) in the cancer cells, a type of precision drug treatment calledtargeted therapymay be used to attack the tumor cells.
• Stage 3: For this stage, doctors typically order some combination ofsurgery, chemotherapy, radiation therapy and targeted therapy. If cancer cells are found to contain certain types of proteins, your care team may add immunotherapy, which makes use of the body’s ability to fight cancer by helping the immune system recognize and attack cancer cells.
• Stage 4: These cancers are difficult to treat, and treatment options may depend on your body’s response to the process.

For limited-stage SCLC, treatment may include:

• Chemotherapy
• Radiation therapy
• Surgery (in some cases, this may be performed before chemotherapy and radiation therapy)

For extensive-stage SCLC, primary treatments include:

• Chemotherapy
• Immunotherapy
• Radiation therapy

Patients with either limited- or extensive-stage disease may benefit from clinical trials for new treatments.

Life expectancy: Prognosis

Each cancer and each person is different. To determine a cancer prognosis, researchers calculate how many people with the same type of cancer and stage of cancer are alive five years after diagnosis (aka the five-year survival rate).

According to theACS:

• For NSCLC, the overall five-year survival rate is 25 percent. The survival rate ranges between 7 percent for advanced-stage disease and to 63 percent for early-stage disease.
• For SCLC, the overall five-year survival is 7 percent. The survival rate ranges between 3 percent for extended-stage lung cancer and 27 percent for limited-stage.

Keep in mind that these rates are based on past years of statistics and may not reflect advances in treatment or new treatments that may be available in clinical trials.

Learn about treatment options for lung cancer