Allo-SCT for myelofibrosis: reversing the chronic phase in the JAK inhibitor era?

At present, allogeneic hematopoietic stem cell transplantation (allo-SCT) is the only curative treatment for patients with myelofibrosis (MF). Unfortunately a significant proportion of candidate patients are considered transplant ineligible due to their poor general condition and advanced age at time of diagnosis. The approval of the first JAK inhibitor, Ruxolitinib, for patients with advanced MF in 2011 has had a qualified impact on the treatment algorithm. The drug affords substantial improvement in MF-associated symptoms and splenomegaly but no major effect on the natural history. There has, therefore, been considerable support to assess the drug’s candidacy in the peri-transplant period. The drug’s precise impact on clinical outcome following allo-SCT is currently not known; nor is the drug’s long term efficacy and safety known. Considering the rarity of MF and the small proportion of patients who are undergoing allo-SCT, well designed collaborative efforts are required. In order to address some of the principal challenges, an expert panel of laboratory and clinical experts in this field was established, and an independent workshop held during the 54(th) American Society of Hematology’s meeting in New Orleans, USA, on 6(th) December 2013 and the European Hematology Association meeting in Milan, Italy on 13(th) June 2014. This document summarizes the results of these efforts.