淋巴结比率用于Ⅲ期直肠癌患者的预后评价

Lymph node ratio for evaluating the prognosis of patients with stageⅢrectal cancer

目的比较第八版美国癌症联盟/国际抗癌联盟的直肠癌淋巴结分期(N分期)、阳性淋巴结比率(LNR)和阳性淋巴结对数比率(LODDS)3种淋巴结分期系统评估新辅助放疗后的Ⅲ期直肠癌患者预后的准确性。方法回顾性分析9616例接受新辅助放疗后的Ⅲ期直肠癌手术的患者,基于淋巴结检取总数是否充足,将患者分为不充足组(n<12)和充足组(n≥12)。利用线性趋势评估分期系统的单调性,似然比检验评估同质性,利用Akaike信息准则(AIC)和受试者工作特征(ROC)曲线评估不同分期方法的相对判别能力。结果3种淋巴结分期方法均被确认为总生存率的独立预后因素,而无论淋巴结检取总数是否充足,LNR分期方法都具有最佳的预后评估作用。结论与LODDS和pN分期方法相比,LNR分期方法预测新辅助放疗后的Ⅲ期直肠癌患者预后准确性最佳,有望成为TNM分期方法的补充或替代。

Objective To compare the accuracy of the eighth edition of AJCC/UICC lymph node staging(N staging),positive lymph node ratio(LNR)and positive lymph node logarithm(LODDS)ratio staging methods in evaluating the prognosis of stageⅢcolorectal cancer patients after neoadjuvant radiotherapy.Methods A retrospective analysis was performed among 9616 stageⅢrectal cancer surgery patients who had undergone neoadjuvant radiotherapy.Based on the adequacy of the total number of lymph node dissection,the patients were divided into inadequate group(n<12)and adequate group(n≥12).Linear trend was used to evaluate the monotonicity of the staging system,the likelihood ratio test was used to evaluate the homogeneity,and the Akaike information criterion(AIC)and subject operating characteristic curve(ROC curve)were used to evaluate the relative discrimination ability of different staging methods.Results All three lymph node staging methods were identified as independent prognostic factors for overall survival,and LNR staging method had the best prognosis regardless of whether the total number of nodes detected was sufficient or not.Conclusion Compared with LODDS and pN staging methods,LNR staging method has the best accuracy in predicting the prognosis of stageⅢrectal cancer patients after neoadjuvant radiotherapy and is expected to be a supplement or substitute for TNM staging method.