Ono T, Sato H, Miyasaka Y, Hagiwara Y, Yano N, Akamatsu H, Harada M, Ichikawa M. Correlation between dose-volume parameters and rectal bleeding after 12 fractions of carbon ion radiotherapy for prostate cancer. World J Radiol 2024; 16(7): 256-264 [PMID: 39086610 DOI: 10.4329/wjr.v16.i7.256]
Corresponding Author of This Article
Takashi Ono, MD, PhD, Doctor, Department of Radiation Oncology, Faculty of Medicine, Yamagata University, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan. abc1123513@gmail.com
Research Domain of This Article
Medicine, Research & Experimental
Article-Type of This Article
Retrospective Study
Open-Access Policy of This Article
This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (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/
Takashi Ono, Hiraku Sato, Yasuhito Hagiwara, Natsuko Yano, Hiroko Akamatsu, Mayumi Harada, Mayumi Ichikawa, Department of Radiation Oncology, Faculty of Medicine, Yamagata University, Yamagata 990-9585, Japan
Yuya Miyasaka, Department of Heavy Particle Medical Science, Yamagata University Graduate School of Medical Science, Yamagata 990-9585, Japan
Author contributions: Ono T designed and performed the research and wrote present paper; Sato H designed and supervised the report; Miyasaka Y provided clinical advice; Hagiwara Y, Yano N, Akamatsu H, Harada M, and Ichikawa M contributed to data analysis.
Institutional review board statement: This study was reviewed and approved by the Ethics Committee of the Faculty of Medicine at Yamagata University (approval number: 2023-51).
Informed consent statement: Patients were not required to give informed consent to the study because the analysis used anonymous clinical data that were obtained after each patient agreed to treatment by written informed consent. When consenting to treatment, we also informed patients of the possibility of their use in research, and they agreed to this, so we do not believe it is necessary to obtain new consent for this study. For full disclosure, the details of the study are published on the home page of Faculty of Medicine at Yamagata University.
Conflict-of-interest statement: All authors report no relevant conflicts of interest for this article.
Data sharing statement: Data sharing is not applicable to this article.
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: Takashi Ono, MD, PhD, Doctor, Department of Radiation Oncology, Faculty of Medicine, Yamagata University, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan. abc1123513@gmail.com
Received: May 21, 2024 Revised: July 8, 2024 Accepted: July 10, 2024 Published online: July 28, 2024 Processing time: 63 Days and 21.9 Hours
Abstract
BACKGROUND
Carbon ion radiotherapy (CIRT) is currently used to treat prostate cancer. Rectal bleeding is a major cause of toxicity even with CIRT. However, to date, a correlation between the dose and volume parameters of the 12 fractions of CIRT for prostate cancer and rectal bleeding has not been shown. Similarly, the clinical risk factors for rectal bleeding were absent after 12 fractions of CIRT.
AIM
To identify the risk factors for rectal bleeding in 12 fractions of CIRT for prostate cancer.
METHODS
Among 259 patients who received 51.6 Gy [relative biological effectiveness (RBE)], in 12 fractions of CIRT, 15 had grade 1 (5.8%) and nine had grade 2 rectal bleeding (3.5%). The dose-volume parameters included the volume (cc) of the rectum irradiated with at least x Gy (RBE) (Vx) and the minimum dose in the most irradiated x cc normal rectal volume (Dx).
RESULTS
The mean values of D6cc, D2cc, V10 Gy (RBE), V20 Gy (RBE), V30 Gy (RBE), and V40 Gy (RBE) were significantly higher in the patients with rectal bleeding than in those without. The cutoff values were D6cc = 34.34 Gy (RBE), D2cc = 46.46 Gy (RBE), V10 Gy (RBE) = 9.85 cc, V20 Gy (RBE) = 7.00 cc, V30 Gy (RBE) = 6.91 cc, and V40 Gy (RBE) = 4.26 cc. The D2cc, V10 Gy (RBE), and V20 Gy (RBE) cutoff values were significant predictors of grade 2 rectal bleeding.
CONCLUSION
The above dose-volume parameters may serve as guidelines for preventing rectal bleeding after 12 fractions of CIRT for prostate cancer.
Core Tip: This study identified the risk factors for rectal bleeding, including dose–volume parameters of 51.6 Gy [relative biological effectiveness (RBE)] in 12 fractions of carbon ion radiotherapy (CIRT) for prostate cancer. The cutoff values of D2cc = 46.46 Gy (RBE), V10 Gy (RBE) = 9.85 cc, and V20 Gy (RBE) = 7.00 cc were significant factors for the occurrence rate of grade 2 rectal bleeding. When planning CIRT for prostate cancer, the rate of rectal bleeding may decrease if these values are used.
