阴茎癌改良病理N分期在中国人群中的预测价值

The roles of prognosis of modified pathological N staging system for Chinese patients with penile cancer

目的探讨加入腹股沟淋巴结转移个数及腹股沟转移侧数的阴茎癌改良病理N分期在中国人群患者中的预测价值。方法回顾性分析1999年3月至2013年1月中山大学附属肿瘤医院团队治疗的246例阴茎鳞状细胞癌患者的临床及病理资料。所有患者均接受原发灶处理及改良根治腹股沟淋巴结清扫术治疗并采用标准化方式收获淋巴结(清扫淋巴结数目≥8枚)。Kaplan-Meier法进行疾病特异性生存率(DSS)分析并采用Log-rank检验进行比较,Cox比例风险模型进行多因素分析。卡方检验、AIC标准和C-index一致性系数进行预测模型的评估。Bootstrap再抽样法(500次)进行模型验证。结果最终111例阴茎癌患者纳入分析。按照国际抗癌联盟-美国癌症联合委员会(UICC-AJCC)的第7版病理N分期标准,pN1、pN2、pN3患者3年DSS分别为89.6%、65.9%、33.6%(P_(N1-N2)=0.030,P_(N2-N3)<0.001,P<0.001);按照改良病理分期标准,pN1、pN2、pN3患者3年DSS分别为90.7%、60.5%、31.4%(P_(N1-N2)=0.005,P_(N2-N3)=0.004,P<0.001)。在多种Cox多因素分析中,仅改良病理N分期具有预测价值(HR:4.877,10.895;P=0.018,<0.001)。模型评估结果显示改良病理N分期系统在中国人群中的预测准确性显著增加。结论阴茎癌改良病理N分期可以更好地预测中国人群患者的预后。阴茎癌改良病理N分期可有利于指导个体化治疗。

Objective To determine the predictive value of a modified pathological N staging system for Chinese patients with penile cancer.Methods The clinical and histopathological data of 246 penile cancer patients with lymph node metastasis treated during March1999 and Jan.2013 were retrospectively analyzed.The eligibility criteria were histologically confirmed penile squamous cell carcinoma and bilateral inguinal lymph node dissection（ILND）with≥8 LNs harvested.Multivariate Cox proportional hazard regressions were used to determine the impact of the clinical and pathological factors on patients’diseasespecific survival.Predictive accuracy was further assessed by the concordance index（the likelihood ratio,Akaike information criterion and the concordance index）.Bootstrap corrected C-indexes were used to internal validation for better gauge expected future predictive accuracy（500 times sampling）.Results Based on the 7th pathological N classification,the 3-year diseasespecific survival for pN1,pN2,and pN3 patients were 89.6%,65.9%,and 33.6%,respectively（PN1-N2 =0.030,PN2-N3 〈0.001,P〈0.001）.Under the modified pathological N category criteria,the 3-year disease-specific survival for pN1,pN2,and pN3 patients were 90.7%,60.5% and 31.4%,respectively（PN1-N2=0.005,PN2-N3=0.004,P〈0.001）.In separate multivariate Cox regression models,only modified N stages（HR：4.877,10.895;P=0.018,P〈0.001）exhibited independent effects on outcome.The accuracy of modified pathological N category was significantly increased.Conclusion The modified pathological N staging system may increase the accuracy of survival prediction and help avoid overtreatment in Chinese patients with penile cancer.