Refined cytogenetic-risk categorization for overall and leukemia-free survival in primary myelofibrosis: a single center study of 433 patients.

We have previously identified sole +9, 13q- or 20q-, as 'favorable' and sole +8 or complex karyotype as 'unfavorable' cytogenetic abnormalities in primary myelofibrosis (PMF). In this study of 433 PMF patients, we describe additional sole abnormalities with favorable (chromosome 1 translocations/duplications) or unfavorable (-7/7q-) prognosis and also show that other sole or two abnormalities that do not include i(17q), -5/5q-, 12p-, inv(3) or 11q23 rearrangement are prognostically aligned with normal karyotype, which is prognostically favorable. These findings were incorporated into a refined two-tired cytogenetic-risk stratification: unfavorable and favorable karyotype. The respective 5-y…