The role of allogeneic SCT in primary myelofibrosis: a British Society for Blood and Marrow Transplantation study

Fifty-one patients with primary myelofibrosis (PMF) received allogeneic haematopoietic stem cell transplants from related ( n =33) or unrelated ( n =18) donors. Twenty-seven patients, 19–54 years old, were prepared with myeloablative regimens including CY plus BU ( n =4) or TBI ( n =23). Twenty-four patients, 40–64 years old, received reduced-intensity conditioning (RIC) regimens. All RIC regimens contained fludarabine, combined with melphalan ( n =19) or BU ( n =5), and alemtuzumab or anti-thymocyte globulin (ATG) in the majority ( n =19). Four patients (17%) in the RIC group had primary graft failure. Previous splenectomy reduced time to engraftment in the RIC group (13 versus 20 days; P =0.008). For MA and RIC groups, respectively, at 3 years, overall survival rates were 44 and 31% ( P =0.67), progression-free survival 44 and 24% ( P =0.87), and actuarial relapse rates 15 and 46% ( P =0.06). Non-relapse mortality at 3 years was 41% for the myeloablative and 32% for the RIC group. Acute GVHD occurred in 29 and 38% of patients in the myeloablative and RIC groups, respectively. Extensive chronic GVHD developed in 30 and 35% of evaluable patients, respectively.