Chronic Lymphocytic Leukemia - The Leukemia & Lymphoma Society

Medical Terms
Allogeneic Stem Cell Transplantation. A treatment that uses donor stem cells
to restore a patient’s marrow and blood cells. First, the patient is given conditioning
therapy (high-dose chemotherapy or high-dose chemotherapy with total body
radiation) to treat the leukemia and to “turn off” the patient’s immune system
so that the donor stem cells will not be rejected. A type of transplant called a
“nonmyeloablative” or “reduced-intensity” transplant is under study. It uses lower
doses of conditioning therapy and may be safer, especially for older patients. For more
information, see the free LLS booklet Blood and Marrow Stem Cell Transplantation.
Anemia. A decrease in the number of red cells and, therefore, the hemoglobin
concentration in the blood. This results in a diminished ability of the blood to carry
oxygen. If severe, anemia can cause a pale complexion, weakness, dizziness, fatigue
and shortness of breath on exertion.
Antibodies. Proteins released by plasma cells (derived from B lymphocytes) that
recognize and bind to specific foreign substances called “antigens.” Antibodies
coat, mark for destruction or inactivate foreign particles, such as bacteria, and
viruses or harmful toxins. Antibodies can also be made in the laboratory, in two
ways. Material from species is injected into a different species; the receiving species
recognizes the materials as foreign and make antibodies to it. These antibodies are
usually polyclonal antibodies; that is, they react to multiple targets (antigens). The
second method involves monoclonal antibodies, which react to only one target
(antigen) and can be used in several important ways. They can be used to identify
and classify types of blood cancers or they can be altered to make them useful in
antibody-mediated immunotherapy.
Apheresis. The process of removing certain components of a donor’s blood and
returning the unneeded parts to the donor. The process, also called “hemapheresis,”
circulates blood from a donor through a specialized machine, and then back to the
donor. Apheresis makes it possible to remove desired elements from large volumes
of blood. Platelets, red cells, white cells and plasma can be removed separately. This
procedure is also used to remove circulating blood stem cells, which can be frozen,
stored and later used for transplantation instead of marrow stem cells. See Platelet
Transfusion.
Autologous Stem Cell Transplantation. A treatment that uses a patient's
own stem cells to delay the progression of certain blood cancers. The autologous
transplantation process takes place after the patient achieves a complete response
(remission), or a good partial response, to induction drug therapy. In this treatment
1) the patient’s stem cells are harvested, usually from the blood; 2) the stem cells
are frozen for later use and the patient receives conditioning drug therapy; and
3) the stem cells are thawed and infused back into the patient through an
indwelling catheter (central line). Patients receive supportive care to help prevent
Chronic Lymphocytic Leukemia I page 29