How many types of cancer are there?

There are more than 100 types of cancer, according to the National Cancer Institute.

Types of cancer are usually named for the organ or tissue where the cancer forms. For example, lung cancer starts in the lung, and brain cancer starts in the brain. Cancers may also be named for the type of cell that formed them, such as an epithelial cell or a squamous cell.

There are also broad groups based on the kind of cell where the cancer begins. Carcinomas are the most common type, and they form in epithelial cells. Sarcomas form in bone and soft tissue, and leukemias begin in blood-forming tissue. Lymphomas begin in the white blood cells that fight disease, and multiple myeloma begins in plasma cells. Melanoma begins in the cells that make skin pigment. Brain and spinal cord tumors are a group of their own, and so are germ cell tumors and neuroendocrine tumors.

Knowing which type of cancer a person has is a key first step. It shapes how the cancer is understood and how care is planned. A health care team can explain the exact type.