Retrospective Cohort Study
Copyright ©The Author(s) 2020. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Aug 21, 2020; 26(31): 4624-4638
Published online Aug 21, 2020. doi: 10.3748/wjg.v26.i31.4624
Impact of interval between neoadjuvant chemoradiotherapy and surgery in rectal cancer patients
Shi-Wen Mei, Zheng Liu, Fang-Ze Wei, Jia-Nan Chen, Zhi-Jie Wang, Hai-Yu Shen, Juan Li, Fu-Qiang Zhao, Wei Pei, Zheng Wang, Xi-Shan Wang, Qian Liu
Shi-Wen Mei, Zheng Liu, Fang-Ze Wei, Jia-Nan Chen, Zhi-Jie Wang, Hai-Yu Shen, Juan Li, Fu-Qiang Zhao, Wei Pei, Zheng Wang, Xi-Shan Wang, Qian Liu, Department of Colorectal Surgery, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China
Author contributions: Mei SW, Chen JN, and Wang ZJ designed the research; Wei FZ, Shen HY, Li J, and Zhao FQ collected the data; Pei W, Wang Z, Liu Z, and Wei FZ analyzed the data; Mei SW drafted the manuscript; Liu Q and Wang XS revised the paper.
Supported by the National Key Research and Development Plan "Research on Prevention and Control of Major Chronic Non-Communicable Diseases", No. 2019YFC1315705; and the Medicine and Health Technology Innovation Project of Chinese Academy of Medical Sciences, No. 2017-12M-1-006.
Institutional review board statement: Our investigation received approval from the ethics committee of the National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College.
Informed consent statement: All study participants or their legal guardian provided informed written consent about personal and medical data collection prior to study enrolment.
Conflict-of-interest statement: The authors declare that there is no conflict of interest in regard to this research.
Data sharing statement: No additional data are available.
STROBE statement: The authors have carefully read the STROBE statement checklist of items and prepared the manuscript based on the requirements of the STROBE statement checklist of items.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Corresponding author: Qian Liu, MD, Chief Doctor, Professor, Surgeon, Department of Colorectal Surgery, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, No. 17 Panjiayuan Nanli, Chaoyang District, Beijing 100021, China. fcwpumch@163.com
Received: May 26, 2020
Peer-review started: May 26, 2020
First decision: June 4, 2020
Revised: June 7, 2020
Accepted: August 1, 2020
Article in press: August 1, 2020
Published online: August 21, 2020
Processing time: 86 Days and 21.7 Hours
Abstract
BACKGROUND

Epidemiologically, in China, locally advanced rectal cancer is a more common form of rectal cancer. Preoperative neoadjuvant concurrent chemoradiotherapy can effectively reduce the size of locally invasive tumors and improve disease-free survival (DFS) and pathologic response after surgery. At present, this modality has become the standard protocol for the treatment of locally advanced rectal cancer in many centers, but the optimal time for surgery after neoadjuvant therapy is still controversial.

AIM

To investigate the impact of time interval between neoadjuvant therapy and surgery on DFS and pathologic response in patients with locally advanced rectal cancer.

METHODS

A total of 231 patients who were classified as having clinical stage II or III advanced rectal cancer and underwent neoadjuvant chemoradiation followed by surgery at the National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College from November 2014 to August 2017 were involved in this retrospective cohort study. The patients were divided into two groups based on the different time intervals between neoadjuvant therapy and surgery: 139 (60.2%) patients were in group A (≤ 9 wk), and 92 (39.2%) patients were in group B (> 9 wk). DFS and pathologic response were analyzed as the primary endpoints. The secondary endpoints were postoperative complications and sphincter preservation.

RESULTS

For the 231 patients included, surgery was performed at ≤ 9 wk in 139 (60.2%) patients and at > 9 wk in 92 (39.8%). The patients’ clinical characteristics, surgical results, and tumor outcomes were analyzed through univariate analysis combined with multivariate regression analysis. The overall pathologic complete response (pCR) rate was 27.2% (n = 25) in the longer time interval group (> 9 wk) and 10.8% (n = 15) in the shorter time interval group (≤ 9 wk, P = 0.001). The postoperative complications did not differ between the groups (group A, 5% vs group B, 5.4%; P = 0.894). Surgical procedures for sphincter preservation were performed in 113 (48.9%) patients, which were not significantly different between the groups (group A, 52.5% vs group B, 43.5%; P = 0.179). The pCR rate was an independent factor affected by time interval (P = 0.009; odds ratio [OR] = 2.668; 95%CI: 1.276-5.578). Kaplan-Meier analysis and Cox regression analysis showed that the longer time interval (> 9 wk) was a significant independent prognostic factor for DFS (P = 0.032; OR = 2.295; 95%CI: 1.074-4.905), but the time interval was not an independent prognostic factor for overall survival (P > 0.05).

CONCLUSION

A longer time interval to surgery after neoadjuvant therapy may improve the pCR rate and DFS but has little impact on postoperative complications and sphincter preservation.

Keywords: Interval time; Advanced rectal cancer; Disease-free survival; Pathologic complete response; Neoadjuvant therapy; Surgery; Complication; Sphincter preservation

Core tip: The time interval between neoadjuvant therapy and surgery is an underlying debate. This study mainly analyzed the effect of prolonging the time interval to surgery after neoadjuvant therapy on pathologic response and disease-free survival. Our study concluded that time interval > 9 wk will result in better prognosis and oncologic outcomes than time interval ≤ 9 wk. In practice, we should prolong the time interval to obtain favorable outcomes in advanced rectal cancer after neoadjuvant therapy.