OBJECTIVETo investigate the clinical and hematological features and prognostic factors of primary myelofibrosis (PMF) patients in Shanghai and surrounding area of Shanghai, China.

METHODSThe clinical manifestations, laboratory parameters and survival were retrospectively analyzed in 75 PMF patients diagnosed from Jan, 1996 to Dec, 2013 in our hospital and were compared with those of Chinese subjects from Tianjin and foreign Caucasian patients, respectively. Comparison of categorical variables was performed by χ² test. Survival was estimated using the Kaplan- Meier method. Log- rank test was used to compare survival date. A Cox model was used for multivariate analyses.

RESULTSThe median age of the 75 patients was 56(19-81) years old. There were 51(68%) patients with HGB less than 100 g/L. The median value of HGB was 83 g/L. Similar with those from Tianjin, the patients in our study were significantly younger with higher proportion of severe anemia and lower platelet counts when compared with foreign Caucasian patients. Using IPSS and dynamic international prognostic scoring system (DIPSS) model, the survival curves of intermediate- 1, intermediate- 2 and high risk groups were significantly different. In univariate analyses, variables significantly correlated with poor prognosis were systemic symptoms, HGB<100 g/L, HGB<80 g/L, PLT ≤ 100 × 10⁹/L, WBC<10 × 10⁹/L and blood blasts ≥ 0.01. Multivariate analysis identified IPSS and HGB < 80 g/L as independent risk factors for survival.

CONCLUSIONChinese PMF patients may have characteristics of younger age at onset with more severe anemia. However, IPSS and DIPSS model are still suitable for Chinese patients to predict survival. To increase the weight of anemia severity may provide a better prognostic stratification for Chinese patients with PMF.