The Transplant Process
Unlike solid organ transplants (e.g., kidney, heart, liver), the BMT procedure is relatively simple. Before beginning the BMT procedure, diagnostic tests are performed to confirm that the patient is medically eligible for BMT. Bone marrow or peripheral blood is collected (harvested) via a needle inserted into the pelvic bone or a blood vessel, respectively. Both bone marrow and peripheral blood contain the stem cells that are capable of producing all of the cells made by bone marrow. The bone marrow harvest is usually performed as an outpatient procedure with the use of local anesthesia and peripheral blood stem cells are collected with a procedure called pheresis. The transplant cells may be processed in the laboratory and autologous marrow is stored by freezing. High doses of chemotherapy and/or radiation are usually given to the patient in order to destroy cancer cells or the defective bone marrow. The normal bone marrow and immune system are also destroyed. However, low doses of chemotherapy and/or radiation that suppresses the immune system and allows the transplant to take (non-myeloablative or 'mini-BMT' ) can now sometimes be used. The bone marrow or peripheral blood transplant is delivered intravenously like a blood transfusion and the stem cells find their way to the bone marrow to produce new blood cells. Management of the complications of BMT (e.g., infections, graft-versus-host disease [GVHD]) is the most difficult part of the BMT process. Blood transfusions, antibiotics, and other drugs will help support the patient until new bone marrow grows, usually within 2 to 5 weeks. Patients are cared for on one of the inpatient units, or as outpatients in our IPOP program.
Diseases Treated
- AML, ALL, CML, CLL
- Non-Hodgkins lymphoma
- Hodgkins disease
- Multiple Myeloma
- Myelodysplastic Syndrome
- Solid tumors: Breast cancer , Ovarian cancer, Testicular cancer, Pediatric solid tumors
- Anemias: Aplastic Anemia, Fanconi Anemia, Paroxysmal Nocturnal Hemoglobinuria
- Inherited diseases: immune deficiencies, metabolic disease, hemoglobinopathies
- Severe autoimmune diseases
Types of Transplants Offered
Syngeneic. The donor is an identical twin of the patient. This is the simplest source of stem cells. Syngeneic transplants are the least complicated transplants because there is no risk of rejection, graft-versus-host disease (GVHD), or tumor in the marrow. Blood cell recovery and return of immunologic function is prompt. The only disadvantage of syngeneic transplants is the lack of the graft-versus-leukemia (GVL) effect of allogeneic transplants that helps reduce tumor relapse.
Allogeneic. The donor, either a relative (usually a brother or sister) or an unrelated individual from a registry, is genetically similar to the patient. Allogeneic transplants have the lowest risk of tumor relapse because of the GVL effect. For more information on GVL, click here. However, GVHD, graft failure, and immune deficiency are potential problems ,especially with unrelated transplants.
Autologous . The patient's own marrow or peripheral blood is used. Autologous transplants are the most commonly performed transplants. Like syngeneic transplants, there is no risk of rejection or GVHD, and the GVL effect is absent. There is the additional concern of tumor contamination of the transplant. This may be a relatively minor concern for certain solid tumors but is a major problem for all blood cancers and some solid tumors. Johns Hopkins has pioneered methods to 'purge' or remove tumor cells from autologous transplants, as well as methods to reduce relapse similar to the allogeneic GVL effect.
Graft Engineering
A critical aspect of the BMT program at Johns Hopkins is the Graft Engineering Laboratory. This laboratory processes all stem cell products for transplantation, and is a world-renowned leader in innovative approaches for improving the safety and efficacy of stem cell products. Click here for more information on the GEL.
New Approaches Being Developed At Johns Hopkins
Clinical Protocols
Inpatient Services Available
Patients undergoing BMT who need inpatient care are treated on one of the inpatient units by a multidisciplinary team who are specialized in the treatment of patients undergoing BMT. The nursing staff is highly trained in the care of BMT patients and in critical care. The units are capable of providing conventional and intensive care. All rooms are private with special air-filtering to decrease the risk of infections. Some patients undergoing BMT now receive their transplants as outpatients in our new IPOP unit.
Outpatient Services Available
A major new innovation in BMT at Hopkins has been the development of outpatient BMT. Click here for information about outpatient transplantation in our new IPOP unit. |
