Interesting work is going on in Memphis. At the Baptist Cancer Center Malignant Hematology and Transplant Program, they are utilizing an innovative new technique that allows individuals with leukemia to receive stem cell transplants without a direct sibling donor or non-related tissue match donor.
Typically a patient with leukemia can try to get a stem cell transplant to strengthen their immune system, helping them fight off disease. But that patient needs a donor that is a 100% tissue match or the transplant could be rejected. The mismatched graft could develop into what is called GVHD, or Graft Versus Host Disease. GVHD develops when the donor’s immune cells begin to attack the patient’s normal cells.
At the Baptist Cancer Center Malignant Hematology and Transplant Program, they have begun using a new procedure which is called a “Haploidentical,” or half-matched transplant. The first patient to undergo this procedure received stem cells donated from her son, and the match was only 50%.
Haploidentical transplants are an option when a 100% match is not readily found. Among Caucasians, roughly 50% find a donor among their direct family or through various donor databases such as MUD. The chances of finding a match are even worse for African-Americans at 10% and Asian-Americans at 5%. In cases where there is no apparent 100% match, a Haploidentical Transplant is an option with a donor pool coming from immediate family members, parents, bothers-sisters, and children.
There are other advantages with Haploidentical Transplants, such as the speed in which the transplant can take place. As opposed to the traditional methods where it could take a few months, a Haploidentical Transplant can take place in a few weeks. This is a big advantage for individuals with aggressive forms of cancer.
During the transplant of blood stem cells, these “undefined” cells are introduced into the patient’s body and they will turn into blood cells, replenishing a weakened immune system and allowing the patient’s body to fight cancer.
Still, GVHD, Graft Versus Host Disease, is a big concern; so individuals are given a chemotherapy drug known as Cyclophosphamide. Cyclophosphamide has two different names it is sold under — Cytoxan and Neosar. Cyclophosphamide is used to treat cancer and autoimmune diseases, and it is an alkylating agent of the nitrogen mustard type. It interferes with DNA replication.
In fact, it is the use of Cyclophosphamide that is one of the biggest concerns in a Haploidentical Transplant, as the side effects of Cyclophosphamide can be severe. That aside, the use of Haploidentical Transplants has opened options up to many who thought they were ineligible for a transplant because they did not have a 100% match.