[A long-term follow-up study on recurrence and benefit of standardized postoperative chemotherapy of rectal cancer patients with complete pathological response after neoadjuvant chemoradiotherapy].

Objective: To analyze the clinicopathological factors affecting long-term disease-free survival and the characteristics of local recurrence or distance metastasis of rectal cancer patients with complete pathological response after neoadjuvant chemoradiotherapy. Methods: The clinicopathological data and follow-up information of patients with a complete pathological response of rectal cancer after neoadjuvant chemoradiotherapy in the Cancer Hospital of Chinese Academy of Medical Sciences from June 2004 to December 2019 were retrospectively collected. The clinicopathological factors affecting the long-term disease-free survival of patients were analyzed to build a prediction model of local recurrence and distant metastasis and to evaluate the benefits of postoperative chemotherapy. Results: The age of 108 patients was(56.3±11.6) years, of which 68 were males (63.0%); The median follow-up time was 79.9 (61.8, 112.6) months. There were 12 patients (11.1%) who had a local recurrence or distant metastasis. The 5-year disease-free survival rate was 91.1% with 9 patients who experienced recurrence. Multivariate Cox proportional hazards regression analysis showed that the maximum diameter of the residual tumor or scar (HR=8.41, 95%CI: 1.08-65.22, P=0.042) and the distance from the lower edge of the tumor to the anal margin before treatment (HR=4.54, 95%CI: 1.23-16.81, P=0.023) were independent risk factors affecting the prognosis. The prognosis of patients was stratified based on relevant factors. The 5-year cumulative disease-free survival rate of those patients receiving postoperative standardized chemotherapy was 92.0%, while for patients who did not receive or complete standardized chemotherapy, the 5-year cumulative disease-free survival rate was 82.3%. Conclusions: The maximum diameter of the residual tumor or scar and the distance from the lower edge of the tumor to the anal margin before treatment were independent risk factors affecting the prognosis of patients with a complete pathological response. Patients with independent risk factors could benefit from the standardized postoperative chemotherapy.目的： 分析直肠癌新辅助放化疗后病理完全缓解患者长期随访中复发的相关因素及规范化疗的获益情况。 方法： 回顾性收集2004年6月至2019年12月在中国医学科学院肿瘤医院接受新辅助放化疗病理完全缓解的108例直肠癌患者的临床病理资料及随访信息，分析患者长期无病生存的临床病理特点及复发的相关因素，同时评估术后规范化疗获益情况。 结果： 108例病理完全缓解患者的年龄为（56.3±11.6）岁，其中男性68例（63.0%）；随访时间［M（Q1，Q3）］为79.9（61.8，112.6）个月。12例（11.1%）患者出现复发，5年内有9例患者出现复发，5年无病生存率为91.1%（99例）。多因素分析发现，术后病理残存肿块或瘢痕最大直径（HR=8.41，95%CI：1.08~65.22，P=0.042）、治疗前肿瘤距肛缘距离（HR=4.54，95%CI：1.23~16.81，P=0.023）是患者术后是否复发的相关因素。根据相关因素将患者进行预后分层，存在上述相关因素的患者，接受术后规范化疗患者5年累积无病生存率为92.0%，未接受化疗或者未完成规范化疗患者为82.3%，差异有统计学意义（P=0.048）。 结论： 术后病理残存肿块或瘢痕最大直径、治疗前肿瘤距肛缘距离是患者术后是否复发的相关因素，存在该因素的患者可以从术后规范化疗中获益。.