Oncology is a branch of medicine that deals with the prevention, diagnosis, and treatment of cancer. Oncologists are doctors who diagnose, assess, treat and manage patients with cancers.

Cancer is a large group of diseases that can start in almost any organ or tissue of the body when abnormal cells grow uncontrollably, go beyond their usual boundaries to invade adjoining parts of the body and/or spread to other organs through a process called metastasis. A neoplasm and malignant tumor are other common names for cancer.

Cancer, when diagnosed early, is treatable through surgery, chemotherapy, radiotherapy or other treatment options.