There are over 200 types of cancers; most can fit into the following categories according to the National Cancer Institute:

• Carcinoma: Cancer that begins in the skin or in tissues that line or cover internal organs



• Sarcoma: Cancer that begins in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue
  
  
• Leukemia: Cancer that starts in blood-forming tissue such as the bone marrow and causes large numbers of abnormal blood cells to be produced and enter the blood



• Lymphoma and myeloma: Cancers that begin in the cells of the immune system



• Central nervous system cancers: Cancers that begin in the tissues of the brain and spinal cord

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