Cancer Fighters Thrive is a quarterly print and online magazine bringing readers practical, innovative and inspirational information about cancer treatment and survivorship.
Issue link: http://cancerfightersthrive.epubxp.com/i/259111
spring 2014 | cancer fighters thrive 45 cf thrive. com Stephen spent about three weeks in the hospital after the transplant. "You do a lot of thinking and put a lot of stuff into per- spective when you're alone for three weeks in a room," he says. Now that he is home, he is waiting for the 100-day mark, which is when the bone marrow matures. At that point he will have a bone marrow biopsy to evaluate his re- sponse to the treatment. Allogeneic Transplantation Allogeneic transplantation is a more risky procedure. "You only take this risk be- cause there is no other choice," explains Dr. Abutalib. "It's that simple and that complicated." With allogeneic transplantation, patients may or may not receive high-dose chemo- therapy; the strength (high dose versus reduced intensity) of chemotherapy relies on many extremely important patient and disease-specifc variables, Dr. Abutalib says. The preparative regimen should work to destroy or damage the patient's immune system so that it can accept or welcome the donor cells and build a new immune sys- tem from them. Once the recipient's (pa- tient's) immune system is made dormant with the aid of the preparative regimen and ongoing constant immunosuppres- sion, a member of the transplant team infuses the patient with donor-matched hematopoietic stem cells. These stem cells can come from an unrelated donor or a sibling, parent or child—or from cord blood. The transplant physician is able to perform a blood test to determine whether the stem cells will match. (See sidebar to learn more about donor cells.) The patient receives the stem cells through a drip, similar to a blood transfu- sion, over a period lasting from a few min- utes to a few hours, during which time the stem cells enter the bloodstream and cir- culate. The success of a transplant is mea- DONATING STEM CELLS The key to allogeneic stem cell transplantation is fnding donor-matched stem cells. These cells can come from an unrelated donor; a sibling, par- ent or child; or umbilical cord blood. A sibling sharing the same mother and father has the best chance of being a match—one in four. A child, on the other hand, has a 100 percent chance of being a half-match. The chance of an unrelated donor's being a match is rarer: about one in 1,000 or 10,000, if they have a common type; and about one in 1 million or 1 billion, if they have an uncommon type. The National Marrow Donor Program (NMDP) has registered more than 4 million donors around the world, and the chances of fnding a donor through NMDP (if a sibling is not matched) are good. Blood type is not the same as bone marrow or stem cell type, so a donor does not need to have the same blood type to be a match. Doctors can per- form a simple blood test to determine if a sibling is a stem cell match. As with any medical procedure, there is a small risk associated with being a donor. Some patients can become a little anemic, but they can take iron pills to combat that. Donors who undergo bone marrow harvest might ex- perience some soreness in the hip for a few weeks, but most people can go back to work within a couple of days. "Anyone who is reasonably healthy can donate stem cells if they want to," Dr. Topolsky says. "The rigors of being a donor are not that bad. It's a nice thing to do and is a lifesaving deed." There is no long-term efect from donating. The bone marrow completely recovers itself within four to six weeks—in fact, a donor could donate again at that point. "They are always looking for people to donate [see sidebar "Resources"]. It's just a matter of having a blood test and then going into the registry," Dr. Topolsky explains. "You can donate, your body recovers from it and makes up those stem cells and you are no worse for the wear." sured through a multistep evaluation over time. Usually, 30 days after transplant "chimera" testing is performed on either bone marrow aspirate or blood. A 100 percent chimera denotes that that patient has successfully engrafted the donor's cells, creating a "new" immune system, explains Dr. Abutalib. At this point the desired outcome is that the new immune system will recognize the cancer cells as "different" and attack them, a reaction known as "graft-versus- cancer effect." The flip side of this is that the immune system could also see normal cells as "different" and attack those. This is referred to as "graft-versus-host disease" (GVHD) and is a serious complication of allogeneic transplantation. The treatment for GVHD is immunosuppressive drugs— medications that suppress the immune re- sponse—and patients are monitored more closely for infections during this time. Dr. Topolsky explains that if a patient dies after an allogeneic transplant, it is usually the re- sult of an infection related to the treatment of GVHD. "Allogeneic transplantation is not com- parable to autologous transplantation. The cftSp#23vky.indd 45 2/3/14 11:18 PM