What is leukemia?

Blood cell cancer: Leukemia is cancer of one of the bone marrow cells. The cells start growing quickly and either enter the blood stream where they are first detected or build up in the bone marrow where people are diagnosed after becoming ill from infection or bleeding because the normal blood cells are crowded out and can't do their jobs. Granulocytes, lymphocytes, red cells and platelets can turn cancerous.

Cancer: Camcer of blood cells or bone marrow.

Blood cancer: Generally speaking, leukemia is a form of cancer, more specifically a cancer that usually originates in the bone marrow and then spreads into the blood. There are many different types and subtypes with their own particularities.