The lungs are an important part of the respiratory system, enabling us to breathe. Lung cancer is the uncontrolled growth of abnormal cells in one or both lungs, usually in the cells lining air passages. These abnormal cells do not develop into healthy lung tissue, but divide rapidly to form tumours which interfere with lung function.
In Singapore, lung cancer is the 2nd most common cancer in men, and the 3rd most common cancer in women. The risk of developing lung cancer is 3 times higher in men as compared to women.
There are 2 main types of lung cancer:
Non-small cell lung cancer (NSCLC)
Non-small cell lung cancer (NSCLC) accounts for the majority of all lung cancers and is less aggressive. Early detection with prompt treatment can offer a chance of cure. Treatment may involve a combination of treatment methods such as surgery, radiation therapy and chemotherapy.
Small cell lung cancer (SCLC)
Small cell lung cancer is an aggressive form of lung cancer which usually results in the rapid spread of cancer to other parts of the body through the bloodstream. SCLC is usually diagnosed at advanced stages, with treatment usually prescribed in the form of chemotherapy.
What causes lung cancer?
Studies have shown that people with certain risk factors are more likely to develop lung cancer. Tobacco smoke exposure, one of the main risk factors, contributes to over 80% of global lung cancer incidence. Tobacco smoke emitted from cigarettes, pipes or cigars contains harmful chemicals known as carcinogens – a class of compounds directly responsible for damaging cells and affecting the cell’s ability to function and to divide normally. Over time, the damaged cells may become cancerous. Even exposure to second-hand smoke can lead to cell damage that aids in cancer formation. The more exposure to tobacco smoke, the greater the risk of developing lung cancer.
Other risk factors include exposure to radon (a radioactive gas), asbestos, arsenic, chromium, nickel, and air pollution. Some families have a higher risk of developing lung cancer.