Frequently Asked Questions

Natural history of a disease may vary from child to child and BMT may not be appropriate for everyone who suffers from the same disease. Some of the diseases that have been treated with BMT include the following:

• leukemia
• lymphomas
• solid tumors (i.e., neuroblastoma, Wilms' tumor, brain tumors)
• aplastic anemia
• sickle cell disease
• thalassemia
• Blackfan-Diamond anemia
• metabolic/storage diseases (i.e.,Hurler's syndrome, adrenoleukodystrophy disorder)
• histiocytosis

Stem cell transplants can be divided according to the type of donor and the source of stem cells for transplantation. If the stem cells are derived from bone marrow, the procedure is called Bone Marrow Transplant. On the other hand, if the source of stem cells is the bloodstream, it is commonly termed as Peripheral Blood Stem Cell Transplant. 

Autologous blood and marrow transplants use the patient's own stem cells. Allogenic blood and marrow transplants use suitably matched donor's stem cells.

In an autologous BMT, it is important to first clear the patient's bone marrow or blood of the underlying disease. Then, the doctor will remove and store the patient's own blood or bone marrow in order to preserve healthy stem cells. This process of collection is also called a harvest. Next, the patient will receive the conditioning therapy to destroy any remaining disease. Following conditioning, the stored stem cells will be given back to the patient so that the bone marrow function can be reconstituted. 

In an allogenic BMT, bone marrow is taken from another individual. Either a relative or an unrelated donor who is suitably matched will donate bone marrow or blood stem cells to be given to the patient, who is also known as the recipient. Just as in an autologous BMT, the recipient will receive conditioning therapy before being given the donor stem cells.

In a third type of stem cell transplant, called umbilical cord blood transplantation, stem cells taken from the blood of a placenta immediately following a delivery are used. The recipient usually receives conditioning therapy prior to receiving the stem cells. The indications for and relative risks and benefits for this type of transplant may be different than the other types of transplant. 

All blood cells evolve from the primitive cells in bone marrow called hematopoietic stem cells or just stem cells. Stem cells are found in a person's bone marrow and in a person's blood.

Once stem cells are given to a patient, they can replicate themselves as well as evolve into mature blood cells, i.e. into red blood cells, white blood cells and platelets. 

Bone marrow is a soft, spongy tissue filling the inside of our bones. It produces the three types of cells that are part of our blood: red blood cells, white blood cells, and platelets. The production and development of new cells is called hematopoiesis. 

Red blood cells (erythrocytes) pick up oxygen in the lungs and transport it to the tissues throughout the body, as well as remove waste products from organs and tissues.

White blood cells (leukocytes) are needed to fight infection.

Platelets are the smallest cell elements in the bloodstream. Platelets are needed to control bleeding. 

High dose chemotherapy and/or radiation (called conditioning therapy) is given to destroy the underlying disease such as leukemia or cancer. However, this conditioning therapy destroys the patient's stem cells as well, without which the body cannot make blood cells. To rescue patients from this lethal side effect of treatment, they are infused or "transplanted" with some of their previously saved stem cells or with stem cells collected from a suitable donor or cord blood. The patient receives the stem cells in the same way that he or she would receive a blood transfusion. 

Sometimes, a BMT is performed to correct a problem with the immune system, a genetic disorder or to provide a supply of a missing enzyme or protein.