Role of Allogeneic Stem Cell Transplant in the Treatment of Primary Myelofibrosis.

OBJECTIVES The only known curative therapy for primary myelofibrosis is allogeneic hematopoietic stem cell transplant. MATERIALS AND METHODS We retrospectively evaluated 11 transplant procedures involving 10 patients (5 men and 5 women) diagnosed with primary myelofibrosis between 2005 and 2014. RESULTS The median age at the time of transplant was 60.5 years (range, 22-62 years). Stem cell sources were unrelated (n=1) and related (n=11) peripheral blood stem cells. Conditioning regimen was myeloablative for 8 and reduced intensity for 3 transplants. The median number of infused CD34+ cells was 6.8 × 106 cells/kg (range, 3.2-10.4 × 106 cells/kg). Neutrophil and platelet engraftment occurred at median of 22 days (range, 12-31 days) and 19.5 days (range, 13-56 days). Acute and chronic graft-versus-host disease was seen in 4 of 11 allografts. Relapse and nonrelapse mortality rates were 20%. Six patients (60%) were still alive without disease after median follow-up of 68.5 months (range, 17-120 months). Median progression-free survival and overall survival were 61 months (range, 2-120 months) and 65 months (range, 2-120 months). CONCLUSIONS Our results suggest that allogeneic hematopoietic stem cell transplant may provide a curative treatment for primary myelofibrosis patients. A myeloablative regimen seems to be effective and safe, especially for younger primary myelofibrosis patients.