ASH evidence-based guidelines: is there a role for second allogeneic transplant after relapse?

A 35-year-old male with a FLT3(+) AML underwent allogeneic peripheral blood stem cell transplant using a myeloablative non-total body irradiation (TBI) conditioning regimen from his HLA-matched sibling donor. Following transplantation, he developed grade II acute graft-versus-host disease (GVHD) that resolved with increasing immunosuppression. The medications were subsequently discontinued, and he did not develop any evidence of chronic GVHD. Eighteen months after transplant, while off all immunosuppression, he developed fatigue and a blood count showed circulating blasts consistent with relapse of his disease. Among the various therapeutic questions is whether there is a role for a second allogeneic transplant to treat his disease and if so, at what time, with what conditioning, and with which type of donor.