Leukemia, lymphoma and myeloma are neoplastic proliferative blood cell disorders. These disorders are considered malignant (cancerous) conditions.
Leukemias usually originate in the bone marrow but can invade other tissues including the lymphatic system, whereas lymphomas originate in the lymphoid tissues, but can invade other tissues including the bone marrow. Leukemias frequently involve the white blood cells, although red blood cells and platelets can also be involved.
Myelomas are a more specific type of disease in that the malignancy involves plasma cells which are specific lymphocytes that have already recognized and responded to antigen, and are often located in the bone marrow.
Two major groupings of leukemia are acute leukemias and chronic leukemias.
