Retrospective Study
Copyright ©The Author(s) 2022. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Oncol. May 15, 2022; 14(5): 1027-1036
Published online May 15, 2022. doi: 10.4251/wjgo.v14.i5.1027
Improving the accuracy and consistency of clinical target volume delineation for rectal cancer by an education program
Yang-Zi Zhang, Xiang-Gao Zhu, Ma-Xiaowei Song, Kai-Ning Yao, Shuai Li, Jian-Hao Geng, Hong-Zhi Wang, Yong-Heng Li, Yong Cai, Wei-Hu Wang
Yang-Zi Zhang, Xiang-Gao Zhu, Ma-Xiaowei Song, Kai-Ning Yao, Shuai Li, Jian-Hao Geng, Hong-Zhi Wang, Yong-Heng Li, Yong Cai, Wei-Hu Wang, Department of Radiation Oncology, Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Peking University Cancer Hospital & Institute, Beijing 100142, China
Author contributions: Zhang YZ drafted the manuscript, and was involved with data analysis; Zhu XG, Yao KN, Li S, and Geng JH participated in the collection and analysis of the data; Song MX, Wang HZ, and Li YH revised the article critically for important intellectual content; Wang WH and Cai Y participated in the design of the study and revision of the article; and all authors read and approved the final manuscript.
Supported by the Beijing Municipal Science & Technology Commission, No. Z181100001718192; the Capital’s Funds for Health Improvement and Research, No. 2020-2-1027 and No. 2020-1-4021; the National Natural Science Foundation, No. 82073333; and the Beijing Natural Science Foundation, No. 1212011.
Institutional review board statement: This study was reviewed and approved by the Beijing Cancer Hospital Research Ethics Committee (Approval No. 2021YJZ111).
Informed consent statement: The participants of the study were not required to give informed consent to the study because the analysis used anonymous image data that were obtained from the education program.
Conflict-of-interest statement: The authors declare that there is no conflict of interest.
Data sharing statement: The datasets used and/or analyzed during the current study are available from the corresponding authors on reasonable request.
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: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Wei-Hu Wang, MD, Chief Physician, Department of Radiation Oncology, Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Peking University Cancer Hospital & Institute, No. 52 Fucheng Road, Haidian District, Beijing 100142, China. wangweihu88@163.com
Received: December 10, 2021
Peer-review started: December 10, 2021
First decision: January 12, 2022
Revised: January 24, 2022
Accepted: April 24, 2022
Article in press: April 24, 2022
Published online: May 15, 2022
ARTICLE HIGHLIGHTS
Research background

Accurate target volume delineation is essential for precise radiotherapy. Inappropriate target volume may reduce local control or bring more normal tissue damage. However, defining a radiation field is not easy since it requires an integration of knowledge from multiple disciplines and rich clinical experience.

Research motivation

Previous studies have proved that wide variations in clinical target volume (CTV) delineation for rectal cancer were present among radiation oncologists despite the availability of several guidelines. Thus, how to improve the delineation accuracy and consistency has emerged as a key question in the era of precise radiotherapy. However, no study regarding the current situation of CTV delineation for rectal cancer is available in China, and there is also a lack of study on the impact of educational interventions on rectal cancer target delineation.

Research objectives

To examine the interobserver variation (IOV) in CTV delineation for rectal cancer among radiation oncologists in mainland China and evaluate whether an education program could improve the accuracy and consistency of delineation.

Research methods

The study consisted of a baseline CTV delineation, a 150-min education intervention, and a follow-up CTV delineation. CTVs contoured by the participants before and after the program were obtained and compared. Quantitative evaluation included the indices for measuring the delineation accuracy of the participants relative to the standard contour and the indices for assessing IOV. Qualitative analysis included four common problems in CTV delineation.

Research results

Eighteen radiation oncologists from 10 provinces in China attended the education program and 13 of them completed two sets of CTVs. After the education program, a statistically significant reduction in the average volume of the delineated CTVs was detected (P = 0.001). The agreement between the participants’ delineation and the standard CTV improved remarkably and the IOV decreased. Qualitative analysis indicated that 61.54% of the participants (8/13) delineated the external iliac area, and 53.85% of the participants (7/13) delineated the ischiorectal fossa unnecessarily at the baseline, and the proportions reduced significantly after the program.

Research conclusions

Our study first confirmed the wide variations in CTV delineation for rectal cancer among radiation oncologists from mainland China and proved that education interventions could improve the accuracy and consistency of delineation.

Research perspectives

Further studies need to recruit more participants and include more cases for target volume delineation. Besides, the long-term effects of the education program also need to be investigated.