What Is Lung Cancer?

Lung cancer is a disease of uncontrolled cell growth in lung tissue. This growth can lead to metastasis, which is an invasion of adjacent tissue and infiltration beyond the lungs. Most primary lung cancer is carcinoma of the lung, derived from epithelial cells. Lung cancer, the most common cause of cancer-related deaths in men and women, responsible for 1.3 million deaths worldwide each year.

The main types of lung cancer lung small cell carcinoma and non-small cell carcinoma of the lung. This distinction is important, because treatment varies, non-small cell carcinoma of the lung (NSCLC) is sometimes treated with surgery, while cells of small lung cancer (SCLC) usually responds better to chemotherapy and radiation. The most common cause of lung cancer is long-term exposure to tobacco smoke.