Lung Cancer

Lung cancer is a cancer that starts in the lungs. People who smoke have the highest risk of lung cancer. Treatment can include surgery, chemotherapy, radiation therapy, or targeted therapy.

Lung Cancer Overview

Reviewed: May 22, 2014
Updated: 

Lung cancer is a cancer that starts in the lungs. The lungs are a pair of cone-shaped organs inside the chest that allow you to breathe. The lungs bring oxygen into the body when you breathe in and send carbon dioxide out of the body when you breathe out.

Cigarette smoking causes most lung cancers. The more cigarettes you smoke per day and the earlier you started smoking, the greater your risk of lung cancer. High levels of pollution, radiation, and asbestos exposure may also increase your risk of developing lung cancer.

Lung cancer is one of the most common cancers in the world. It is the leading cause of cancer death in men and women in the United States. Lung cancer accounts for about 27% of all cancer deaths, and lung cancer claims more lives each year than colon, prostate, ovarian and breast cancers combined.

The 2 main types of lung cancer are non-small cell lung cancer and small cell lung cancer. The types of cancer are based on the way the cells look under a microscope. Non-small cell lung cancer is much more common than small cell lung cancer. Non-small cell lung cancer is an umbrella term for several types of lung cancers that behave in a similar way. Non-small cell lung cancers include squamous cell carcinoma, adenocarcinoma and large cell carcinoma. Small cell lung cancer occurs almost exclusively in heavy smokers and is less common than non-small cell lung cancer.

Treatment for lung cancer depends on the type, stage, and how advanced it is. Treatments include surgery, chemotherapy, radiation therapy, and targeted therapy. For most patients with lung cancer, current treatments do not cure the cancer.

Lung Cancer Symptoms

Lung cancer typically does not cause signs and symptoms in its earliest stages. Signs and symptoms of lung cancer typically occur only when the disease is advanced. Common symptoms of lung cancer include:

  • a cough that does not go away and gets worse over time
  • changes in a chronic cough, such as a "smoker's cough"
  • constant chest pain
  • coughing up blood, even a small amount
  • shortness of breath, wheezing, or hoarseness
  • repeated problems with pneumonia or bronchitis
  • swelling of the neck and face
  • loss of appetite or weight loss for no apparent reason
  • fatigue
  • bone pain
  • headache

Lung Cancer Causes

Smoking causes the majority of lung cancers — both in smokers and in people exposed to secondhand smoke. Smoking causes lung cancer by damaging the cells that line the lungs.

Lung cancer also occurs in people who never smoked and in those who never had prolonged exposure to secondhand smoke. In these cases, there may be no clear cause of lung cancer.

In general, cancer occurs when cells in your liver develop errors (mutations) in their DNA. The errors make cells grow and divide out of control. The accumulating abnormal cells form a tumor in the lung that can grow to invade nearby structures and spread to other parts of the body.

Factors that increase your risk for lung cancer include:

  • smoking
  • exposure to secondhand smoke
  • exposure to radon gas
  • exposure to asbestos and other carcinogens
  • family history of lung cancer

Lung Cancer Diagnosis

In order to diagnose lung cancer, your doctor may recommend:

  • imaging tests. X-ray images of your lungs or a CT scan can reveal masses or small lesions in your lungs.
  • sputum cytology. If you have a cough and are producing sputum, looking at the sputum under the microscope can sometimes reveal the presence of lung cancer cells.
  • tissue sample (biopsy). A sample of abnormal cells may be removed from the lung in a procedure called a biopsy.

Living With Lung Cancer

If you have or have had lung cancer, you can take steps to manage the stress that accompanies the diagnosis.

  • Learn about lung cancer so you can make informed decisions about your care.
  • Have a schedule of follow-up tests and go to each appointment.
  • Take care of yourself so that you are ready to fight cancer. This includes eating a healthy that includes plenty of fruits, vegetables and whole grains, exercising for at least 30 minutes most days of the week, and getting enough sleep so that you wake feeling rested.
  • Accept help and support from family and friends and talk with a counselor, social worker, or clergy member.

Many people with lung cancer experience shortness of breath at some point in the course of the disease. Treatments, such as supplemental oxygen, and medications are available to help you feel more comfortable.

Lung Cancer Treatments

After lung cancer is found and staged, your physician will discuss treatment options with you. The treatments will be based on your overall health and the extent and location of the cancer.

Lung cancer treatment options may include:

Surgery. Surgery is performed to remove a portion of the lung or the entire lung.

Ablation. Radiofrequency ablation uses high-energy radio waves to destroy the cancer cells.

Chemotherapy. Chemotherapy uses drugs to kill cancer cells. Chemotherapy options for lung cancer include:

Radiation therapy. Radiation therapy uses high-powered energy beams to destroy cancer cells and shrink tumors.

Targeted drug therapy. Targeted therapy interferes with a tumor's ability to generate new blood vessels. Targeted therapy options for treating lung cancer include:


Lung Cancer Prognosis