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.
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STELLAR Ⅲ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。.