不同血小板水平原发性骨髓纤维化患者的临床特征及预后研究

OBJECTIVE: To evaluate clinical characteristics and prognosis of primary myelofibrosis (PMF) patients with thrombocytopenia in varied degrees. METHODS: Clinical features and survival data of 1 305 Chinese patients with PMF were retrospectively analyzed. The prognostic value of thrombocytopenia in patients with PMF was evaluated. RESULTS: 320 subjects (47％) presented severe thrombocytopenia (PLT<50×10(9)/L), 198 ones (15.2％) mild thrombocytopenia [PLT (50-99)×10(9)/L] and 787 ones (60.3％) without thrombocytopenia (PLT ≥ 100×10(9)/L). The more severe the thrombocytopenia, the higher the proportions of HGB<100 g/L, WBC<4 × 10(9)/L, circulating blasts ≥ 3％ , abnormal karyotype and unfavourable cytogenetics (P<0.001, P<0.001, P＝0.004, P<0.001 and P<0.001, respectively) were observed in this cohort of patients. The more severe the thrombocytopenia, the lower the proportion of JAK2V617F positive (P<0.001) was also noticed. Platelet count was positively correlated with splenomegaly, HGB and WBC (P<0.001, correlation coefficients were 0.131, 0.445 and 0.156, respectively). Platelet count was negative correlated with constitutional symptoms and circulating blasts (P＝0.009, P＝0.045, respectively; correlation coefficients were -0.096 and -0.056, respectively). The median survival of patients with severe thrombocytopenia, mild thrombocytopenia and without thrombocytopenia were 32, 67 and 89 months, respectively (P<0.001). Multivariate analysis identified thrombocytopenia in varied degrees (HR＝1.693, 95％CI 1.320-2.173, P<0.001) and Dynamic Internation Prognostic Scoring System (DIPSS) prognostic model (HR＝2.051, 95％ CI 1.511-2.784, P<0.001) as independent risk factors for survival. CONCLUSION: PMF patients with severe thrombocytopenia frequently displayed anemia, leucopenia, circulating blasts and short survival, so active treatment measures should be taken especially in these patients.