外周血NK细胞绝对值在慢性淋巴细胞白血病中的预后价值

Prognostic value of absolute NK cell count in peripheral blood of chronic lymphocytic leukemia

目的:探索外周血自然杀伤(NK)细胞绝对值在慢性淋巴细胞白血病(CLL)患者中的分布、与其他临床指标的相关性及其预后价值。方法:回顾性分析2005—2014年126例初诊CLL患者的临床资料。Mann-Whitney U检验及Kruskal-Wallis检验分析NK细胞绝对值与其他临床指标的相关性。生存分析采用Kaplan-Meier法,预后因素分析采用Cox比例风险模型。结果:126例初诊CLL患者外周血NK细胞绝对值的中位值为0.54×10~9个/L(0.01×10~9~4.11×10~9个/L),将NK细胞绝对值0.20×10~9个/L作为预测CLL患者预后的分界值。126例患者中位随访44.5个月,NK细胞绝对值≥0.2×10~9个/L组与<0.2×10~9个/L组的5年总生存率(OS)分别为71.9%和48.4%(P=0.031)。单因素生存分析显示外周血低NK细胞绝对值(<0.20×10~9个/L)与较短的OS相关(P=0.019);多因素生存分析发现NK细胞绝对值对CLL的OS具有独立预后意义(P=0.005)。结论 :初诊CLL患者外周血NK细胞数量可能反映自身免疫水平,NK细胞数量减低提示预后不良。

Objective：To explore the distribution of absolute natural killer（NK） cell count in peripheral blood in patients with chronic lymphocytic leukemia（CLL）,and evaluate correlation with other clinical indicators and its prognostic value. Methods：The information of a total of 126 patients with CLL treated in the First Affiliated Hospital of NJMU from 2005 to 2014 were collected in this retrospective study. Comparisons of NK cell count as continuous parameter in different groups were described using Mann-Whitney U test and the Kruskal-Wallis test. Kaplan-Meier method was used to survival analysis,and the Cox proportional hazards models were used for the estimation of prognostic factors. Result：The median absolute NK cell counts were 0.54×10^9/L（range：0.01×10^9-4.11×10^9/L） in all the 126 CLL cases. The most discriminative cut-points of NK cell counts at diagnosis was defined as 0.20×109/L. With a median follow-up of 44.5 months,patients with NK cell count ≥0.20×10^9/L had a 5-year overall survival（OS） of 71.9%,whereas patients with NK cell count〈0.20×10^9/L had a 5-year OS of 48.4%（P=0.031）. Univariate analysis showed that low NK cell count was associated with inferior OS（P=0.019）,and multivariate analysis confirmed NK cell count as an independent risk factor（P=0.005）. Conclusion：Absolute NK cell count in peripheral blood of CLL patients may reflect level of immunity,the reduction of NK cell count indicate poor prognosis.