Cancer encompasses more than 200 diseases, with different causes, symptoms, and degrees of aggressiveness (the speed of growth and spread). Most types of cancer fall under one of four categories: carcinomas, sarcomas, lymphomas, and leukemias.
Carcinomas
Carcinomas develop in the tissues that cover the surface internal organs and their passageways. These are also called epithelial cancers. They generally develop in an organ that secretes something, such as breast tissue, which secretes milk, or lung tissue, which secretes mucous.
Sarcomas
Sarcomas develop in bone and soft tissue, including muscles, tendons, blood vessels, and nerves. Sarcomas are not confined to certain areas, as supporting and connective tissue is found throughout your body. Organs also contain connective tissues (not just surface tissues) and, as a result, the same organ that develops a carcinoma can also develop a sarcoma.
Lymphomas
Lymphomas affect the lymphatic system (a system of vessels used to flush toxins from your body) and tumours detected within are almost always malignant. One type of lymphoma is called Hodgkin's Disease, while all of the others are generally described as non-Hodgkin's lymphomas (although there are many sub-categories of each).
Leukemias
Leukemias are cancers affecting white blood cells and are named after the type of white blood cell affected. For instance, plasma cell myeloma is a leukemia affecting plasma cells in the bone marrow.
