Oncology is a branch of medicine that deals with cancer. “Onco” means bulk, mass, or tumor while “logy” means study. Each of the cells of the body have a tightly regulated system that controls their growth, maturity, reproduction and eventual death. Cancer begins when cells in a part of the body start to grow out of control. There are many kinds of cancer, but they all start because of out-of-control growth of abnormal cells. This book focus on the recent progress and research on oncology and serves as an essential guide for oncologists. Oncologists are medical professionals who practice oncology. These oncologists have several specific roles. They help in diagnosis of the cancer, help in staging the cancer and grading the aggressive nature of the cancer.