Dynamic International Prognostic Scoring System (DIPSS) predicts progression to acute myeloid leukemia in primary myelofibrosis

Primary myelofibrosis (PMF) is a myeloproliferative neoplasm (MPN) with a high propensity to develop acute myeloid leukemia, named at this stage blast phase (BP) of PMF. 1 Oncogenic JAK2 signaling is an important event in MPN, but transformation process into BP, although not completely understood, often involves additional genomic lesions. 2 Several models have been developed to predict survival in PMF. 3-5 Concerning BP occurrence, leukocyte count more than 30 10 9 /L, 5 blast cell count more than 10%, 6 platelet count below 50 10 9 /L, 6 red blood cell transfusion dependency, 7 selected cytogenetic abnormalities, 6,8 low JAK2(V617F) allele burden 9 have been reported to shorten BP-free survival.