NCCN Guidelines for Patients® | Chronic Myeloid Leukemia
24 NCCN Guidelines for Patients ® : Chronic Myeloid Leukemia, 2018 3 Overview of cancer treatments Hematopoietic cell transplant Hematopoietic cell transplant Blood (hematopoietic) stem cells are cells from which all blood cells are formed. They mainly exist in bone marrow. Cancer or its treatment can damage or destroy blood stem cells. A stem cell transplant replaces damaged or destroyed stem cells with healthy stem cells. An allogeneic stem cell transplant uses healthy stem cells from a donor. The donor may be related to you or not. This transplant is also called an allogeneic HCT ( h ematopoietic c ell t ransplant). The healthy stem cells will form into new marrow and blood cells. This creates a new immune system. Another benefit of this transplant is the GVL ( g raft- v ersus- l eukemia) effect. The GVL effect is an attack on cancer cells by the transplanted stem cells. The steps of an allogeneic HCT are briefly described next. HLA typing Special testing must be done to find the right donor for you. The donor and your tissue type must be a near-perfect match for this treatment to work. The test used to check tissue type is called HLA ( h uman l eukocyte a ntigen) typing. A blood sample is needed to perform the test. Conditioning Before the transplant, you will receive treatment that destroys bone marrow cells. The death of the cells creates room for the healthy stem cells. It also weakens your immune system so your body won’t kill the transplanted cells. There are two main types of conditioning treatment. High-dose conditioning consists of high doses of strong chemotherapy. Reduced-intensity conditioning consists of low doses of strong chemotherapy. It may also consist of low-intensity drugs. Radiation therapy may also be given as part of conditioning treatment. High-dose conditioning can cause very bad side effects. It can be deadly. Also, not everybody can tolerate it. Your doctor will decide if you are healthy enough for this treatment. Reduced-intensity conditioning may be used for people who are older or less healthy overall. However, the chance for a cancer relapse is greater. Transplanting stem cells After chemotherapy, you will receive the healthy stem cells through a transfusion. A transfusion is a slow injection of blood products through a central line into a large vein. A central line (or central venous catheter) is a thin tube. The tube will be inserted into your skin through one cut and into your vein through a second cut. Local anesthesia will be used. This process can take several hours to complete. The transplanted stem cells will travel to your bone marrow and grow. New, healthy blood cells will form. This is called engraftment. It usually takes about 2 to 4 weeks. Until then, you will have little or no immune defense. You may need to stay in a very clean room at the hospital. You may be given antibiotics to prevent or treat infection. You may also be given a red blood cell transfusion to prevent bleeding and to treat anemia. Platelet transfusion may be received to treat a low platelet count or bleeding. While waiting for the cells to engraft, you will likely feel tired and weak.