摘要目的 分析病理分期为ⅢA-N2(pⅢA-N2)的非小细胞肺癌(NSCLC)患者行手术±辅助化疗后,加或不加术后放疗(PORT)的疗效,从术前临床因素中筛选能从PORT中获益的亚组人群.方法 回顾性分析2006年1月至2015年12月行根治性手术的pⅢA-N2 NSCLC患者804例.其中,PORT组患者276例,单纯化疗组528例.通过增强CT或者PET/CT获取准确的临床淋巴结分期.CT上淋巴结短径≥10 mm或者PET/CT上淋巴结SUV＞2.5定义为转移淋巴结.PORT使用三维适形或调强放疗技术,计划靶体积的设计处方剂量为50～60 Gy,剂量分割为1.8～2.2 Gy/次.采用Log Rank法进行单因素预后分析,Cox回归进行多因素预后分析及亚组分析,通过Kaplan-Meier法和Log Rank检验评估PORT对总生存(OS)、无病生存(DFS)、无局部区域复发生存(LRFS)和无远处转移生存(DMFS)的影响,并进行亚组分析.结果 全组患者的中位随访时间为32.07个月.2年、5年OS分别为82.1％、54.5％,中位DFS为19.84个月,中位LRFS为120.31个月,中位DMFS为30.52个月.行PORT显著改善了OS(x2=5.253,P=0.022)、DFS(x2=18.397,P＜0.001)、LRFS(x2=15.358,P＜0.001)和DMFS(x2=6.434,P=0.011),且差异均有统计学意义.单因素分析结果显示,男性、年龄≥60岁、术前T分期增加、术前N分期为N1～N2、病理类型为非鳞癌非腺癌、化疗周期为1～2、未行PORT是显著影响OS的不良预后因素.多因素分析结果显示性别、年龄、术前N分期、病理类型、是否PORT为OS相关的独立预后因素;行PORT有OS获益的亚组分别为男性(HR:0.697,95％CI:0.513～0.947,P=0.021)、吸烟(HR:0.648,95％CI:0.464～0.905,P=0.01 1)、术前N分期为N1～N2(HR:0.640,95％CI:0.465～0.881,P=0.006)、临床分期为Ⅲ期(HR:0.688,95％CI:0.484～0.980,P=0.038)以及病理类型为腺癌(HR:0.726,95％CI:0.527～0.999,P=0.049)的患者.结论 PORT能改善全组患者的OS、DFS、LRFS和DMFS.部分术前临床因素具有预测PORT后有OS获益的亚组人群的价值,包括男性、吸烟、术前N分期为N1～N2、临床分期为Ⅲ期以及病理类型为腺癌的患者.

abstractsObjective Pathological ⅢA-N2 non-small-cell lung cancer (pⅢA-N2 NSCLC)is a heterogeneous population,and the role of postoperative radiotherapy(PORT) after the adjuvant chemotherapy (ACT) in pⅢA-N2 NSCLC remains ambiguous.Not all pⅢA-N2 patients can benefit from PORT.This study was performed to identify the subgroup that can benefit from PORT after ACT.Methods This study included 804 p ⅢA-N2 NSCLC patients completing radical resection and ACT from January 2006 to December 2015.The patients were divided into two groups:PORT group,patients who underwent PORT after radical resection and ACT;and NON-PORT group,control group of patients who only underwent radical resection and ACT.The PORT and NON-PORT groups consisted of 276 and 528 patients,respectively.Accurate clinical lymph node staging was obtained through contrast-enhanced CT and/or PET/CT.Lymph nodes measured in the short axis ≥ 10 mm on CT or SUV＞2.5 on PET/CT were considered as metastases.Using 3-dimensional conformal radiation therapy or intensity modulated radiation therapy techniques,PORT was administered at 1.8-2.2 Gy per fraction to a prescription dose to the planning target volume of 50-60 Gy.Outcome measures included overall survival(OS),disease-free survival(DFS),locoregional recurrence-free survival(LRFS),and distant metastasis-free survival(DMFS).Kaplan-Meier,Log Rank test,and Cox regression were used to analyze survival data and identify prognostic factors.Statistically significant difference was set to P＜0.05.Results Median follow-up time was 32.07 months.The 2-year and 5-year OS of the patients in the entire cohort were 82.1％ and 54.5％,respectively.The median values of the DFS,LRFS,and DMFS were 19.84,120.31,and 30.52 months,respectively.In the overall study cohort,the median values of the OS (97.31 months vs.64.10 months,x2=5.253,P=0.022),DFS (25.76 months vs.17.97 months,x2=18.397,P＜0.001),LRFS(120.31 months vs.101.03 months,x2=15.358,P＜0.001) and DMFS(36.83 months vs.28.49 months,x2=6.434,P=0.011) were significantly higher in the PORT group than in the NON-PORT group.Univariate analysis showed that the adverse prognostic factors which significantly affected OS were:male,age ≥ 60 years,advanced preoperative T staging,preoperative N 1-N2,non-squamous carcinoma and non-adenocarcinoma,1-2 chemotherapy cycles and NON-PORT.Multivariate Cox analyses revealed that factors indepeudently associated with longer OS were PORT(HR=0.754,95％CI=0.584-0.973,P=0.03),female,age ＜60 years,preoperative clinical N0,clinic stage Ⅰ-Ⅱ,adenocarcinoma,or squamous carcinoma.Subgroup analysis indicated that several preoperative clinical factors could predict the population that would benefit from PORT after ACT.These factors included male(HR=0.697,95％CI=0.513-0.947,P=0.021),smoking patient(HR=0.648,95％CI=0.464-0.905,P =0.011),preoperative clinical N 1-N2(HR=0.640,95％CI=0.465-0.881,P=0.006),clinic stage Ⅲ(HR=0.688,95％CI=0.484-0.980,P=0.038),and adenocarcinoma(HR=0.726,95％CI=0.527-0.999,P=0.049).Conclusions PORT after ACT could significantly improve the 5-year OS,DFS,LRFS,and DMFS in p Ⅲ A-N2 NSCLC patients.Moreover,PORT could improve the 5-year OS of the subgroups with the following characteristics:male,smoking patient,preoperative clinical N1-N2,clinic stage],and adenocarcinoma.