基于鼻咽癌临床Ⅲ期探讨第8版AJCC/UICC分期系统

Discussion of the 8th edition of AJCC/UICC staging system from the clinical stage Ⅲ nasopharyngeal carcinoma

目的基于调强放疗临床Ⅲ期鼻咽癌的生存分析中探讨第8版AJCC/UICC鼻咽癌分期系统。方法2008-2014年在汕头大学医学院附属肿瘤医院首次治疗的1351例鼻咽癌患者中按第7、8版标准重新分期,确定Ⅲ期患者分别为742、784例,将其各自分为3个亚组:T3N0-1期为G1(226、245例),T1-2N2期为G2(180、187例),T3N2期为G3(336、352例)。Kaplan-Meier法分别计算3个组5年总生存(OS)、无进展生存(PFS)、无远处转移生存(DMFS)、无局部区域复发生存(LRRFS),并log-rank检验组间差异。结果第8版病例中93.6%与第7版的相同。第8版与第7版总体的OS、PFS、DMFS、LRRFS分别为84.8%与85.4%、76.2%与77.0%、80.4%与81.3%、89.8%与90.6%(P均>0.05)。第8版分期3个亚组的OS、PFS和DMFS均不同(P均<0.001);G1与G2、G1与G3也不同(P均<0.05),G2与G3间相近(P=0.183、0.310、0.248)。结论第8版AJCC/UICC分期系统对临床Ⅲ期病例的分布特点及临床终点相对于第7版变化不大,亚组间仍有明显的组内生存风险分布差异,其中N2对Ⅲ期患者的生存风险评估起到主要作用。可能在IMRT联合化疗时代局部肿瘤对预后的影响已经减弱,第8版分期系统仍然有改进的空间。

Objective To evaluate the 8th edition of AJCC/UICC staging system for stageⅢnasopharyngeal carcinoma(NPC)by the survival analysis.All patients were treated with intensity-modulated radiotherapy(IMRT).Methods Among 1351 treatment-naïve NPC patients who received radiotherapy/chemoradiotherapy in our hospital from December 2008 to October 2014,742 and 784 cases were classified as clinical stageⅢbased on the criteria of the 7th and 8th edition of AJCC/UICC staging systems,respectively.These patients were classified into three subgroups according to the 7th and 8th edition of AJCC/UICC staging systems:T3N0-1 as G1(n=226,n=245),T1-2N2 as G2(n=180,n=187)and T3N2 as G3(n=336,n=352).The 5-year overall survival(OS),progression-free survival(PFS),distant metastasis-free survival(DMFS)and local-regional recurrence-free survival(LRRFS)were analyzed with Kaplan-Meier method.The differences among different groups were evaluated by log-rank test.Results There were 93.6%patients evaluated by the 8th AJCC/UICC staging system remained the same cohort with those by the 7th AJCC/UICC staging system.The 5-year OS,PFS,DMFS and LRRFS of the 8th and 7th staging systems were 84.8%and 85.4%,76.2%and 77.0%,80.4%and 81.3%,89.8%and 90.6%,respectively(all P>0.05).The OS,PFS or DMFS significantly differed among three subgroups classified by the 8th staging system(all P<0.001).In addition,statistical significance was observed between G1 and G2,and between G1 and G3(both P<0.05),whereas no statistical significance was noted between G2 and G3(P=0.183,0.310,0.248).Conclusions The distribution features and clinical endpoints of clinical stageⅢdefined by the 8th AJCC/UICC staging system are similar to those defined by the 7th AJCC/UICC staging system.The distribution of survival risk significantly differs among different subgroups.N2 plays a major role in assessing the survival risk of patients with stageⅢNPC.In the era of IMRT plus chemotherapy,the effect of local tumors on clinical prognosis has been diminished.The 8th AJCC/UICC staging system remains to be further improved.