Study demonstrates that bone marrow and PBSC result in similar patient survival

Patients who receive a blood stem cell transplant from a donor outside of their family to treat leukemia and other blood diseases are more likely to have graft failure but less likely to experience graft-versus-host disease if the transplanted blood cells come directly from a donor's bone marrow, rather than from circulating peripheral blood stem cells (PBSCs), according to new research.

Although the study showed differences in the type and extent of complications, the results showed no difference in patient survival rates between these two major sources of donated blood cells. The study, presented in the plenary session of the 53^rd annual American Society of Hematology conference in San Diego, was conducted by the Blood and Marrow Transplant Clinical Trials Network (BMT CTN).

This randomized study, the first to compare outcomes in patients receiving a transplant from an unrelated donor, included nearly 50 transplant centers in the United States and Canada. It compared two-year survival rates for 273 patients receiving PBSC with 278 patients receiving bone marrow. The study found that survival was the same using either blood cell source, but the complications following transplant were different depending on which source was used.

PBSCs resulted in better engraftment than bone marrow, but were associated with higher rates of chronic graft-versus-host-disease (GVHD) (53 percent compared with 40 percent in bone marrow), and the GVHD was also more extensive. GVHD is a serious and often deadly post-transplant complication that occurs when the newly transplanted donor cells recognize the recipient's own cells as foreign and attack them.

"This was an important study to conduct in a randomized, prospective manner. This new research confirms much of what we had seen previously, but now gives patients, donors and physicians more concrete evidence to consider when deciding on the course of treatment," said Dr. Dennis Confer, National Marrow Donor Program (NMDP) chief medical officer, who co-authored the study.

"Our trial demonstrates that bone marrow and PBSC result in similar patient survival. While PBSCs result in better engraftment, this did not lead to a survival benefit in our study follow-up period, but did show an increased risk for chronic GVHD," said lead study author Claudio Anasetti, M.D., chair of the Department of Blood & Marrow Transplant at Moffitt Cancer Center in Tampa, Fla. "More effective strategies to prevent GVHD are needed to improve outcomes in these patients."