What is cancer?

Cancer is one of the four major types of noncommunicable diseases (cardiovascular disease, diabetes, cancer and chronic respiratory diseases). Cancer is the uncontrolled growth of cells, which can invade and spread to distant sites of the body. There are over 100 types of cancer, affecting different parts of the body, and they can be either benign or malignant. A benign tumor does not invade surrounding tissue and is usually not harmful. Malignant tumors can invade nearby tissue and spread to other parts of the body.