Age and platelet count are IPSS‐independent prognostic factors in young patients with primary myelofibrosis and complement IPSS in predicting very long or very short survival

OBJECTIVES: The current study was designed to identify International Prognostic Scoring System (IPSS)-independent prognostic factors in young patients with primary myelofibrosis (PMF). The study also examined the overall risk profile of long-term (>15 yr) and short-term (15-yr survival documented in 16 patients (long-term survivors). Multivariable analysis identified unfavorable IPSS category (intermediate-2/high risk), age >50 yr and platelet count or = 2 risk factors, respectively (P or = 100 x 10(9)/L; the corresponding figures for short-term survivors were 29%, 50% and 65% (P < 0.01). CONCLUSIONS: Age and platelet count are IPSS-independent predictors of survival in young patients with PMF, and they complement the IPSS in identifying patients with very long or very short survival.