What is a bone marrow transplant?

Bone marrow cells, also called "stem cells," produce all the blood cells in the body. Diseases like leukemia, lymphoma and myeloma originate in the bone marrow and lymphatic tissues, which interfere with the body's production of healthy blood cells and makes the body unable to protect itself against infections. 

A blood or bone marrow transplant is a complicated, intensive treatment. Patients undergoing bone marrow transplant first receive high doses of chemotherapy to destroy the diseased cells in the body. The chemotherapy also destroys the patient’s bone marrow, making it impossible for the patient to produce new blood cells or to fight infection. After the high-dose chemotherapy phase, bone marrow is re-introduced to the patient in a process similar to blood transfusion.