新辅助直肠评分在局部晚期直肠癌新辅助短程放疗后巩固化疗模式中的预后及辅助化疗决策作用

Role of neoadjuvant rectal score in prognosis and adjuvant chemotherapy decision-making in locally advanced rectal cancer following neoadjuvant short-course radiotherapy and consolidation chemotherapy

目的探讨新辅助直肠(NAR)评分在新辅助短程放疗加巩固化疗模式下对局部晚期直肠癌(LARC)预后的影响及对辅助化疗决策的价值。方法选取2015年8月至2018年8月入组STELLARⅢ期试验(NCT02533271)接受新辅助短程放疗加巩固化疗并可计算NAR评分的LARC患者。按照NAR评分,分为低(<8分)、中(8~16分)、高(>16分)组。生存分析采用Kaplan-Meier法和Log rank检验,影响因素分析采用Cox比例风险回归模型。结果232例LARC患者,低、中和高NAR评分患者分别为56例(24.1%)、113例(48.7%)和63例(27.2%)。中位随访37个月,低、中和高NAR评分患者的3年无病生存(DFS)率分别为87.3%、68.3%和53.4%(P<0.001)。多因素分析显示,NAR评分(中NAR评分:HR=3.10,95%CI:1.30~7.37,P=0.011;高NAR评分:HR=5.44,95%CI:2.26~13.09,P<0.001)、切除状态(HR=3.00,95%CI:1.64~5.52,P<0.001)及辅助化疗(HR=3.25,95%CI:2.01~5.27,P<0.001)为DFS的独立预后因素,高NAR评分者DFS显著较低。R0切除患者中,低、中NAR评分者接受辅助化疗的3年DFS率分别为97.8%、78.0%,高于未接受辅助化疗的患者(分别为43.2%和50.6%,均P<0.05)。高NAR评分者接受或未接受辅助化疗的3年DFS差异无统计学意义(分别为54.2%和53.3%,P=0.214)。结论NAR评分是LARC新辅助短程放疗加巩固化疗策略中的有效预后指标,在后续辅助化疗决策方面具有潜在作用,其值得在更大样本量的研究中进一步验证其价值。

Objectives To assess the prognostic impact of the neoadjuvant rectal(NAR)score following neoadjuvant short-course radiotherapy and consolidation chemotherapy in locally advanced rectal cancer(LARC),as well as its value in guiding decisions for adjuvant chemotherapy.Methods Between August 2015 and August 2018,patients were eligible from the STELLAR phase III trial(NCT02533271)who received short-course radiotherapy plus consolidation chemotherapy and for whom the NAR score could be calculated.Based on the NAR score,patients were categorized into low(<8),intermediate(8-16),and high(>16)groups.The Kaplan-Meier method,log rank tests,and multivariate Cox proportional hazard regression models were used to evaluate the impact of the NAR score on disease-free survival(DFS).Results Out of the 232 patients,24.1%,48.7%,and 27.2%had low(56 cases),intermediate(113 cases),and high NAR scores(63 cases),respectively.The median follow-up period was 37 months,with 3-year DFS rates of 87.3%,68.3%,and 53.4%(P<0.001)for the low,intermediate,and high NAR score groups.Multivariate analysis demonstrated that the NAR score(intermediate NAR score:HR,3.10,95%CI,1.30-7.37,P=0.011;high NAR scores:HR=5.44,95%CI,2.26-13.09,P<0.001),resection status(HR,3.00,95%CI,1.64-5.52,P<0.001),and adjuvant chemotherapy(HR,3.25,95%CI,2.01-5.27,P<0.001)were independent prognostic factors for DFS.In patients with R0 resection,the 3-year DFS rates were 97.8%and 78.0%for those with low and intermediate NAR scores who received adjuvant chemotherapy,significantly higher than the 43.2%and 50.6%for those who did not(P<0.001,P=0.002).There was no significant difference in the 3-year DFS rate(54.2%vs 53.3%,P=0.214)among high NAR score patients,regardless of adjuvant chemotherapy.Conclusions The NAR score is a robust prognostic indicator in LARC following neoadjuvant short-course radiotherapy and consolidation chemotherapy,with potential implications for subsequent decisions regarding adjuvant chemotherapy.These findings warrant further validation in studies with larger sample sizes.