ASH Clinical News May 2016 | Page 63

TRAINING and EDUCATION Patient Education UNDERSTANDING TRANSPLANT IN LYMPHOMA Hematopoietic cell transplantation (HCT), also called stem cell or bone marrow transplantation, is a treatment option for patients with blood cancers such as leukemia, multiple myeloma, or lymphoma. Together with radiation therapy or chemotherapy, HCT is designed to increase the chance of eliminating the blood cancer and restore normal blood cell production. Read on to learn more about how HCT is used to treat lymphoma. This “Patient Education” tear sheet was produced in collaboration with the Lymphoma Research Foundation (www.lymphoma.org). What Is Hematopoietic Cell Transplantion? Hematopoietic cell transplantation is a procedure that replaces unhealthy blood-forming cells with healthy cells. A hematopoietic or stem cell is an immature cell in the bone marrow that can develop into mature blood cells. These mature cells maintain a person’s blood cells, replacing older or damaged cells with newer ones. The ability to transplant stem cells allows physicians to use higher doses of chemotherapy to treat the cancer than the body would normally tolerate, because highdose chemotherapy can cause significant damage to stem cells. If the chemotherapy is followed by an infusion of stem cells, these new stem cells can replace the cells in the bone marrow that were destroyed during the chemotherapy treatment. Who Can Receive a Hematopoietic Cell Transplant? High-dose chemotherapy and HCT may place a great strain on a patient’s body, so this is not an option for everyone. This procedure is typically used for patients with relapsed (disease returns after treatment), aggressive lymphoma that is still sensitive to the effects of chemotherapy. The procedure does not work for patients with tumors that are unresponsive to drugs. When deciding if transplantation is a good option, doctors will consider many factors, including the patient’s health status, age, medical history, cancer stage, and response to previous therapy. Types of Hematopoietic Cell Transplants Cut out and give to a patient Autologous Hematopoietic Cell Transplantation In autologous HCT (AHCT), hematopoietic cells are donated by the patient and collected and frozen before the patient undergoes cancer treatment. After cancer treatment is administered and the cancer cells are believed to be gone, the collected stem cells are reinfused back into the patient. Because a patient is receiving his or her own hematopoietic cells, an AHCT ensures a perfect match between the patient and the transplanted cells, which improves outcomes. Additionally, this procedure has a lower risk of transmitting blood-borne infectious diseases. As these donated cells take hold (or engraft) in the recipient, they begin to function as part of the immune system and may attack the cancer cells. This is referred to as graft-versus-tumor effect, which only occurs in AlloHCT. In some cases, the donor cells also attack the patient’s healthy cells. This is called graft-versus-host disease (GVHD). The more closely related the donor’s cells are to the patient’s cells, the lower the risk of GVHD. Reduced-Intensity Transplantation Reduced-intensity transplantation (also called non-myeloablative or mini-allogeneic transplantation) is a type of allogeneic transplantation. Unlike a standard allogeneic transplant, this treatment uses lower doses of chemotherapy and/or radiation to prepare the patient for the transplant. The reduced-intensity treatment kills some of the cancer cells and bone marrow, and it suppresses the patient’s immune system just enough to allow the donor’s stem cells to settle into the bone marrow. These types of transplants are used in patients with adverse health conditions or older patients to avoid the potential adverse effects of destroying bone marrow during standard high-dose chemotherapy (with or without radiation). Sources of Hematopoietic Cells for Transplantation Hematopoietic cells for transplantation can be obtained from three sources: bone marrow, peripheral blood, and umbilical cord blood. Bone Marrow Bone marrow, the tissue inside bones where blood cells are generated, is a good source of hematopoietic cells, and cells from the pelvis or hip bone are most often used Allogeneic Hematopoietic Cell Transplantation In allogeneic HCT (AlloHCT), the hematopoietic cell donor is not the patient, but rather another person who is genetically similar – often a sibling – though it is possible for the donor to be unrelated to the patient. After the patient has undergone chemotherapy and/or radiation therapy, the donor’s hematopoietic cells are infused into the patient. ASHClinicalNews.org ASH Clinical News 61