Locally advanced rectal mucinous adenocarcinoma: is preoperative radiation necessary?

作者：Biao Li, Ketong Wu, Jian Li, Qianyu Wu, Yue Wu, Xinhua Wang, Yu Linghu, Huabin Hu, Huaiming Wang, Wuteng Cao · 发表于：Journal of Gastrointestinal Oncology · 年份：2022 · DOI：10.21037/jgo-22-817 · 被引用次数：3 · 研究领域：Colorectal Cancer Surgical Treatments、Colorectal and Anal Carcinomas、Intraperitoneal and Appendiceal Malignancies

Background: Neoadjuvant chemoradiotherapy is recommended for locally advanced rectal cancer, allowing preoperative down-staging of the primary tumor to facilitate complete surgical removal. However, further investigation is warranted for identifying whether radiotherapy is necessary for rectal mucinous adenocarcinoma (RMAC). Thus, this study was designed to explore the relationship between mFOLFOX6 with or without preoperative radiotherapy and therapeutic efficacy in locally advanced RMAC. Methods: A total of 81 patients were retrospectively enrolled, with MRI-defined clinical stage II/III RMAC received neoadjuvant treatment with mFOLFOX6 alone (group A) or mFOLFOX6 plus radiation (group B), followed by total mesorectal excision. Tumor down-staging and tumor response were assessed based on post-treatment MRI-defined radiographical and pathological findings. Follow-up data were retrieved, and the Kaplan-Meier curve was used to determine the relationship between the 3-year disease-free survival (DFS) and overall survival (OS) in the two groups. Results: There were no significant differences in the clinical baseline characteristics of patients between group A and group B. The sphincter preservation rate in group B was 60.9%, higher than in group A (20.0%) (P=0.031). The rate of pathological complete response (pCR) was 14.0% in group B, while no patients had pCR in group A (P=0.029), and the tumor response rate in group B was higher than in group A (52.0% vs. 16.1%, P=0.001). The...