Stem cell transplantation refers to transplants of blood-forming stem cells taken from the bone marrow or collected from the bloodstream. Autologous transplants use the patient’s own stem cells, while allogeneic transplants use stem cells provided by a donor. Stem cell transplants offer some patients with blood-related cancers such as leukemia, lymphoma, and multiple myeloma the possibility of a cure, and others a longer period of disease-free survival.
Patients may be eligible for a transplant if their cancer responds to chemotherapy and/or radiation treatment. In an autologous transplant, high doses of chemotherapy and/or radiation therapy kill cancer cells throughout the body — with the side effect of destroying the bone marrow, where stem cells produce new blood cells. The transplanted stem cells “rescue” the patient by rebuilding the bone marrow and regenerating the blood supply.
Allogeneic transplants can also involve high doses of chemotherapy and/or radiation therapy. The stem cells transplanted from a donor produce white blood cells that launch an anti-cancer attack of their own — called the graft-versus-leukemia effect. Another type of allogeneic transplant, known as a reduced intensity transplant, uses lower doses of chemotherapy to create space in the bone marrow for the new, donor stem cells to grow. White blood cells made from the donor cells do the brunt of tumor cell killing.
Whether cancers can be cured by transplants is a question with a qualified yes,” says Joseph Antin, MD, chief of Stem Cell Transplantation, Emeritus, at Dana-Farber. “Certainly, all hematological malignancies have the potential to be cured with allogenic stem cell transplantation,” he says. “We also do autologous transplants with the intent of curing Hodgkin lymphoma and non-Hodgkin lymphoma, testicular cancer, and some ovarian germ cell cancers.”
However, “as a general rule, solid tumors such as breast, colon, and others are not treated with stem cell transplantation,” Antin notes. This is because transplant has not been shown to be effective against these tumor types.
About 50,000 transplants are performed annually, and the number increases by 10-20% every year. More than 20,000 have lived five years or more after having a stem cell transplant.
“We have patients who are now more than 30 years out and cured,” says Antin.
About the Medical Reviewer
Dr. Antin received his MD from Cornell University in 1978, and postgraduate training in hematology and medical oncology at DFCI and Brigham and Women's Hospital. He subsequently served as director of the Bone Marrow Transplantation Service at BWH from 1987 to 1997. He now heads the Stem Cell Transplant Program of the Department of Medical Oncology at DFCI and BWH. He is a founding member and past president of the American Society of Blood and Marrow Transplantation and a past Chairman of the Steering Committee of the BMT Clinical Trial Network.