About Lung Cancer
Cancer occurs when cells in the body undergo a mutation that causes them to grow rapidly and uncontrollably. Lung cancer forms when cancer cells invade and destroy healthy cells in the lung tissues and air passages. There are two main categories of lung cancer: non-small cell lung cancer and small cell lung cancer.
Lung cancer can take several years to develop. It may begin as pre-cancerous changes in the lungs that neither cause symptoms nor show up on an X-ray.
