Validation of the eighth edition of the AJCC staging system for patients with pancreatic adenocarcinoma initially receiving chemoradiotherapy and proposal of modifications

作     者：Xiaofei Zhu Di Chen Yangsen Cao Xianzhi Zhao Xiaoping Ju Yuxin Shen Fei Cao Shuiwang Qing Fang Fang Zhen Jia Huojun Zhang Xiaofei Zhu;Di Chen;Yangsen Cao;Xianzhi Zhao;Xiaoping Ju;Yuxin Shen;Fei Cao;Shuiwang Qing;Fang Fang;Zhen Jia;Huojun Zhang

作者机构：Department of Radiation OncologyChanghai Hospital Affiliated to Navy Medical UniversityShanghai 200433China 

出 版 物：《Cancer Biology & Medicine》 (癌症生物学与医学（英文版）)

年 卷 期：2020年第17卷第2期

页      面：492-500页

核心收录：

学科分类：1002[医学-临床医学] 100214[医学-肿瘤学] 10[医学] 

基　　金：grants from the Special Project of Ministry of Science and Technology(Grant No.2017 YFC0113104) We thank Dr.Jiuhong Chen for helpful comments,Dr.Fabienne Hirigoyenberry and Dr.Huijun Chen,for language editing and LinkDoc for their constructive advice in patient follow-up. 

主　　题：Chemotherapy modifications pancreatic cancer stereotactic body radiation therapy the eighth edition of the AJCC staging system 

摘      要：Objective:To validate the eighth edition of the AJCC staging system in patients with pancreatic adenocarcinoma receiving only stereotactic body radiation therapy and chemotherapy,and to propose modifications to improve prognostic accuracy.Methods:Patients with pathologically confirmed pancreatic adenocarcinoma without metastasis who were undergoing only chemoradiotherapy were included and staged according to the seventh and eighth editions of the AJCC staging system.Meanwhile,another group of stage T4 patients from the above enrollment with only portal vein involvement with or without tumor thrombi(PV±PVTT)were retrieved for survival comparisons.Modifications were proposed according to the survival comparisons.A cohort from the SEER database was used for external validation of the modified staging system.Results:A total of 683 patients were included.Patients with N2 or N1 but different T stages had significantly different survival outcomes according to the eighth edition.The survival of patients with(PV±PVTT)was comparable to that of patients with T4 tumors.The concordance index of the seventh and eighth editions,and the modified staging system was 0.744(95%CI:0.718—0.769),0.750(95%CI:0.725—0.775),and 0.788(95%CI:0.762-0.813),respectively.For external validation,the concordance index was 0.744(95%CI:0.718-0.770),0.750(95%CI:0.724-0.776),and 0.788(95%CI:0.762-0.814),respectively.Conclusions:The modified staging system is suggested to have the m ost accurate prognostic value.Hence,PV土PVTT should be added to the definition of T4 tumors regardless of tumor size.Patients with N2 or N1 in different T stages could be regrouped into different substages.Additionally,stage III should be subclassified into IIIA(T3N 2 and T4N 0)and IIIB(T4N 1-2).