Physical and mental recovery after hematopoietic stem cell transplantation.

Extract: Hematologic malignancies such as leukemia and lymphoma can be treated with high-dose chemotherapy and irradiation, but in many cases, the amount of treatment needed to eliminate malignant cells also destroys normal blood-forming cells in the bone marrow. During the past 35 years, this problem has been solved by hematopoietic stem cell transplantation (HCT). With this strategy, normal marrow function can be restored by the transplanted blood-forming stem cells that are infused like a blood transfusion after high-dose chemotherapy. In allogeneic transplantation, the stem cells come from a healthy donor. In autologous transplantation, the cells are taken from the patient and frozen until they are infused after high-dose treatment has been completed. Along with killing malignant and non-malignant immune cells, the treatment given before HCT also kills other rapidly dividing healthy cells, often causing hair loss, mouth sores and sometimes other organ problems. The immune suppression caused by treatment leaves a patient vulnerable to viruses and bacterial infections. After transplantation, immune reconstitution and resolution of acute complications usually begin within two weeks, but other complications, such as graft-versus-host disease (GVHD) can continue for years. GVHD occurs when the transplanted allogeneic cells attack (attempt to reject) the host body.