Source: National Cancer Institute
Staging is the process of finding out how much cancer is in a person’s body and where it’s located. It’s how the doctor determines the stage of a person’s cancer. For most types of cancer, doctors use staging information to help plan treatment and to predict a person’s outlook (prognosis). Although each person’s situation is different, cancers with the same stage tend to have similar outlooks and are often treated the same way. The cancer stage is also a way for doctors to describe the extent of the cancer when they talk with each other about a person’s cancer.
Each of these stages, except Stage IV, is divided into A, B, and C.