OBJECTIVETo evaluate the prognostic value of cytogenetics in Chinese with primary myelofibrosis (PMF).

METHODSFour hundred and thirty-nine Chinese patients with PMF were retrospectively analyzed. The Kaplan-Meier method, the Log-rank test, the likelihood ratio test and the COX proportional hazards regression model were used to evaluate the prognostic scoring systems.

RESULTSFour hundred and thirty-nine Chinese patients with PMF were analyzed with a median age of 56 years (range: 8-83), including 298 males and 141 females. The DIPSS-plus system could effectively evaluate prognosis in Chinese patients with PMF. There was significantly higher predictive power for survival for the DIPSS-plus group compared with the DIPSS group (P=0.006, -2 log-likelihood ratios of 989.5 and 1001.9 for the DIPSS-plus and DIPSS systems, respectively). Univariate analysis indicated that the patients with a normal karyotype, a complex karyotype that was not a monosomal karyotype, +8 only or a balanced translocation only had better survival. Following two cytogenetic risk categories were constructed: favorable karyotype including subjects with a normal karyotype, a complex karyotype that was not a monosomal karyotype, +8 only or a balanced translocation only and unfavorable karyotype included all others. The modified DIPSS-Chinese prognostic model was proposed by adopting cytogenetic categories and DIPSS- Chinese risk group. The median survival of patients classified in low risk (163 subjects), intermediate-1 risk (187 subjects), intermediate-2 risk (82 subjects) and high risk (7 subjects) were not reached, 74 (95% CI 42-106), 39 (95% CI 26-52) and 12(95% CI 1-25)months, respectively, and there was a statistically significant difference in overall survival among the four risk groups (P<0.01).

CONCLUSIONThe DIPSS-plus had significantly higher predictive power than the DIPSS group in Chinese patients with PMF and the modified DIPSS-Chinese system based on the cytogenetic features of Chinese patients was proposed and worked well for prognostic indication.