Chemotherapy is the use of drugs to treat cancer.
Normal cells grow and die in a controlled way.
But cancer occurs when cells become abnormal and keep dividing and forming more cells without control or order. Anticancer drugs destroy cancer cells by stopping them from growing or multiplying at one or more points in their life cycle. Because some drugs work better together than alone, chemotherapy often may consist of more than one drug. This is called combination chemotherapy . In addition to chemotherapy, other methods sometimes are used to treat cancer.