Lung Cancer


The Disease

Lung cancer is a disease whereby, cells grow uncontrollably in the lung tissue usually beginning in the lining of the bronchi or bronchioles (small tubes in the lungs, through which air passes while breathing). The growth may lead to metastasis, which is when the cancer spreads to other areas of the body. The main types of lung cancer are small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC). This page discusses only NSCLC.

Causes & Risks

Smoking is the most common cause of lung cancer and is attributed to approximately 85% of cases. Lung cancer in non-smokers is attributed to a combination of genetic factors, radon gas, asbestos and air pollution, including second-hand smoke.1

Diagnosis & Screening

If lung cancer is suspected, several tests can be used to see whether or not it is present. Screening and diagnostic tests include physical examinations, chest x-ray, or CT-scan. A more definitive way to diagnose lung cancer is by examining samples of cells or tissues. 1

Disease Management

The main treatments for lung cancer are surgery, radiation therapy, chemotherapy, and targeted therapy. The choice of treatment will depend on the type of lung cancer, whether it has spread beyond the lung and the general health of the patient.


Surgery for lung cancer removes the tissue that contains the tumour and the nearby lymph nodes are also sometimes removed.

Radiation therapy

Radiation therapy uses high-energy rays to kill cancer cells.


Chemotherapy uses drugs to kill cancer cells. These anticancer drugs are usually given through a vein. Usually, more than one drug or a combination of chemotherapy agents are given.

Targeted Therapies

Targeted therapies are newer forms of anticancer treatment. These agents block the growth and spread of cancer cells by interfering with specific molecules involved in this process. 1 By focusing on molecular and cellular changes specific to cancer, targeted cancer therapies may be less harmful to normal cells and more effective than other conventional therapy


  1. National Cancer Institute. Available online at http://www.cancer.govv Accessed 28 March 2011