淋巴结转移率对淋巴结清扫不足15枚胃癌患者预后评估的价值

Prognostic value of metastatic lymph node ratio for gastric cancer patients with less than 15 lymph nodes dissection

目的评价淋巴结转移率（MLR）对淋巴结清扫不足15枚胃癌患者预后评估的价值。方法回顾性分析天津医科大学附属肿瘤医院2003年1月到2007年7月间收治的610例胃癌患者的临床资料。其中淋巴结清扫数目不足15枚者320例，15枚以上者290例．比较两组患者在不同病理N分期（pN分期）和不同淋巴结转移度分期（rN分期）中预后的差异。结果通过Log—rank检验，确定MLR的界值，按此界值可分为rN。（MLR小于或等于10％）、rN：（MLR大于10％，但小于或等于30％）、rN3（MLR大于30％，但小于或等于60％）和rN4（MLR大于60％）4期。对于淋巴结清扫数目不足15枚者，上述不同rN分期患者的生存差异均无统计学意义（均P〉0．05）；在同-rN分期中，不同pN分期之间生存差异亦均无统计学意义（均P〉0．05）。对于pN2和pN3a期患者，淋巴结清扫数目不足15枚者与15枚以上者的生存差异有统计学意义（均P〈0．05）；但在各个rN分期中，两者间差异均无统计学意义（均P〉0．05）。多因素预后分析证实，rN分期是淋巴结清扫数目不足15枚胃癌患者的独立预后因素（P=0．012，RR=1．617，95％CI：1．111～2．354）。结论rN分期能很好地对淋巴结清扫不足15枚胃癌患者的预后进行预测。

Objective To evaluate the prognostic value of metastatic lymph node ratio （MLR） for gastric cancer patients with less than 15 lymph nodes dissected. Methods Clinical data of 610 gastric cancer patients undergoing operation in Tianjin Cancer Hospictal from January 2003 to July 2007 were analyzed retrospectively. Patients were divided into two groups： 〈15 lymph nodes dissected group （n=320） and ≥15 lymph nodes dissected group （n=290）. MLR was classified based on the following intervals： rN1 ≤10%, rN2 10%-30%, rN3 30%-60% and rN4〉60%. Survival was determined by Kaplan-Meier method and difference was assessed by Log-rank test. Multivariate analysis was performed using Cox proportional hazard regression model. Survival rates were compared between two groups in pN and rN stages respectively. Results In 〈15 nodes group, all the survival differences among various rN stages were not significant（all P〉0.05 ）, while in same rN stage, all the survival differences among various pN stages were not significant （all P〉0.05）. Significant differences of 5-year cumulative survival rates were found between the two groups in pN2 and pN3a stage patients（both P〈0.05） while no significant differences were found among different rN stages（all P〉0.05）. Multivariate analysis demonstrated rN stage was an independent prognostic factor for gastric cancer patients with 〈15 lymph nodes dissected （P=0.012, RR=1.617, 95%CI：1.111-2.354）. Conclusion The rN staging system based on MLR can predict the prognosis of astric cancer patients with less than 15 lvmh nodes dissected.