Chief, Medical Oncology Stem Cell Transplant Program, Dana-Farber Cancer Institute
Professor of Medicine, Harvard Medical School
This is actually one of the first stem cell transplantation programs to be started worldwide. We did our first transplant in 1972. Back in those days very few transplants were done per year. We typically did just a few per year. Things have changed rather substantially in the past couple of decades. Now we do in the range of 550 to 570 transplantations a year.
Types of Transplantation
There are two major types of transplantation that we do. The first is called autologous transplantation, meaning that the patient’s own stem cells are used. The second type of transplant that we do is allogeneic, using family members, unrelated donors, umbilical cord blood, matched donors, mismatched donors for a variety of blood diseases, leukemias, lymphomas, congenital disorders and various forms of blood, bone marrow failure. And these are principally done in a couple of situations, the first being those people who have an intrinsic bone marrow disorder. And these are commonly leukemia or other forms of bone marrow failure such as myelodysplastic syndrome or aplastic anemia or even patients who have congenital bone marrow disorder such as thalassemia or sickle cell anemia.
Progress in Transplantation
So if we go back to the early days of transplantation, really the only acceptable donor was a matched sibling – which is great, matched sibling transplantation is a very effective way to go except that with the average family size in the United States of being less than two children per family, the chance of finding a matched donor in a family is less than 25 percent.
So the more people in the registry the better but there are limitations on that as well. And so over the past few years we have devoted our attention to doing transplantation using donors that are only partially matched. And that allowed us to cross HLA barriers; that is to perform successful transplantation using donors that were not fully matched. And cord blood transplantation, since the late 1980s has become a very important part of our armamentarium. But even then we didn’t have enough donors for everybody.
And over just the past few years we sort of cracked the code for how to do mismatched transplantations, that is, to use a brother or a sister who is only half matched, to use a parent as a donor for an offspring who is, for genetic purposes an obligate half-match, or a child to his parent. This is called haploidentical transplantation. And for many years we couldn’t do it. But in the past few years we solved the technical barrier to doing that, and now we can find a donor for just about everyone.
If I look back on my career in 1981, if you were 35, that was the upper age limit where we did transplantation. And that limited us to doing on the order of 20 or 30 transplants a year back in those days. Well, we recognized that it was a problem and that it was a limitation to what we were doing. And as we advanced in our understanding of the basic biology of the diseases, as we improved in our ability to provide supportive care, as we learned how to reduce the side effects of the transplantation, what we call conditioning regimens, the chemotherapy and radiation that are administered, and how better to control graft versus host disease we were able to offer transplantation to older and older people.
So now, for instance, last year we did 570 transplantations. The average age is about 55 or 60. And we’re doing transplantations up until the age of about 75, which I would never have imagined in 1981as a fellow in transplantation.
Transplantation at Dana-Farber/Brigham and Women’s Cancer Center
The future of transplantation, I think looks very bright. We are progressively understanding these diseases more. We are coming up with better antibiotics. As we understand the underlying biology of the diseases we’re able to target those, the frailties of the cancer cell. So while some of these newer therapies may not be curative in and of themselves they may enhance the cure rate when we combine them with transplantation and that’s one of the important places that we’re going.
This is one of the largest transplant programs in the world. And one of the advantages of being in a big program is the experience of the people who work here. Our nurses and our physicians are exposed to a large number of patients who have transplant-related complications and therefore become highly experienced in the management of these complications to a degree that I think you might not see in a smaller center.
It also gives us a critical mass of patients who have kindly volunteered to participate in research activities. And these research activities have, without question improved the outcomes of people who have gone through transplantation. And the more we can leverage that, the more effective we are and the better our outcomes become.