Allogeneic hematopoietic stem cell transplantation (ASCT) is the only curative option for patients with primary myelofibrosis (PMF), but information on the net advantage over conventional therapies is lacking. Using an ad hoc statistical analysis, we determined outcomes in 438 patients younger than 65 years at diagnosis who received ASCT (n=190) or conventional therapies (n=248). Among patients with low risk by Dynamic International Prognostic Scoring System (DIPSS) prognostic model the relative risk of dying after receiving ASCT versus those treated with non-transplant modalities was 5.6 (95% CI: 1.7-19; P=0.0051); for intermediate-1 risk it was 1.6 (95% CI: 0.79-3.2; P=0.19), for intermediate-2, 0.55 (95% CI: 0.36-0.83; P=0.005), and for high risk 0.37 (95% CI: 0.21-0.66; P=0.0007). Thus, patients with intermediate-2 or high risk PMF clearly benefit from ASCT. Patients at low risk should receive non-transplant therapy, while individual counseling is indicated for patients at intermediate-1 risk.
