How many different cancers are there?

There are many different kinds of cancers. In fact, there are as many different cancers as there are tissue types in the body. The diversity of human tissue is incredible and it is possible for cancers to arise from almost any site and many cell types. However, there are probably 20 or so dominant types of cancer.  Although there are many kinds of cancer, they all start because abnormal cells grow out of control. From another point of view, there are as many different types of cancer as there are different types of human cell- just over 200. However, cancers can be broadly grouped into four types, depending on which tissues they come from.

• Carcinomas: arise from the cells that cover external and internal body surfaces. For example, lung, breast, and colon.
• Sarcomas: arise from cells found in the supporting tissues of the body such as bone, cartilage, fat, connective tissue and muscle.
• Lymphomas: arise in the lymph nodes and tissues of the body's immune system.
• Leukaemias: arise from immature blood cells that grow in the bone marrow and tend to accumulate in large numbers in the bloodstream.