What is Lung Cancer?

Lung cancer is the uncontrolled growth of abnormal cells in the lungs. Rather than developing into healthy, normal lung tissue, these abnormal cells continue dividing and form lumps or masses of tissue called tumors which interfere with the main function of lung. These tumors may be benign (slowly growing, non-cancerous) or malignant (rapidly growing, cancerous). The vast majority of primary lung cancer is carcinomas of the lung, derived from epithelial cells. Lung Cancer is the most common cause of death due to cancer causing approximately 1.3 million deaths annually worldwide.