Role of molecular alterations in transplantation decisions for patients with primary myelofibrosis.

The aim of our study was to analyze the potential survival benefit associated with hematopoietic stem cell transplantation (HSCT) according to clinicobiological scores, which incorporate mutation-enhanced international prognostic score system (MIPSS) to facilitate decision-making in this context. One transplant (n = 241) and 1 nontransplant cohort (n = 239) were used to test the hypothesis that patients with primary myelofibrosis with higher risk molecular score benefit from HSCT. A weighted propensity score was applied to balance confounding factors with the transplanted cohort as reference. Weighted Cox proportional hazard models and logistic regression analyses were performed. Overall, 105 patients who did not receive transplant could be matched to the 239 patients who did receive transplants. HSCT was associated with a higher 6-year overall survival rate in intermediate-2 (60.1% vs 41.5%) and high-risk DIPSS patients (44.4% vs 6.55%), high-risk MIPSS70 (46.5% vs 23.9%), high-risk (73.2% vs 39.7%) or very high-risk MIPSS70+V2 (51.8% vs 24%). Patients with intermediate MIPSS70 scores have an advantage of survival with HSCT only when their myelofibrosis transplant scoring system (MTSS) were low or intermediate. Patients who received transplant had an increased mortality risk the first year, but a significant benefit with HSCT after the 1-year landmark was observed in higher risk patients. This study confirms that, similar to DIPSS, MIPSS70 and MIPSS70+V2 risk score in addition to MTSS can be used to determine which patients with primary myelofibrosis have survival benefit from HSCT over non-HSCT strategies.