Evaluation of the changes in hydrogel spacer volume in patients treated with proton therapy for prostate cancer.

IF 1.9 3区医学 Q3 UROLOGY & NEPHROLOGY

BMC Urology Pub Date : 2025-07-07 DOI:10.1186/s12894-025-01845-0

Kuniaki Inoue, Masatake Shinohara, Toshihisa Saka, Yoshihiko Hirao, Yasuhiro Shinohara, Tatsuyuki Higashikawa, Michinori Yamamoto

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引用次数: 0

Abstract

Background: Rectal bleeding is a recognized late complication of radiation therapy in the treatment of prostate cancer, and hydrogel spacers have been used to prevent this adverse effect. Previous reports have indicated that the volume of hydrogel spacers remains stable for at least 3 months after implantation [1]; however, no cases of early resolution have been reported. Therefore, this study aimed to investigate the hydrogel spacer volume changes over time.

Methods: We included 103 patients implanted with hydrogel spacers who underwent proton therapy at our hospital between April 2020 and November 2022. Two patients were excluded due to improper hydrogel spacer placement beyond the prostatic side of Denonvilliers' fascia. To examine the volume of Space OAR, we measured the spacer volume using magnetic resonance imaging at the time of dosimetry treatment planning and again at 7 and 21 fractions in the remaining 101 patients.

Results: Among the 101 patients, four exhibited a significant reduction in spacer volume at 21 fractions, and one of these patients experienced rectal bleeding.

Conclusion: Unexpected early changes in the hydrogel spacer volume may increase rectal exposure from the time of radiation planning.

Clinical trial number: Not applicable.

Abstract Image

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前列腺癌质子治疗患者水凝胶间隔体积变化的评价。

背景：直肠出血是前列腺癌放射治疗的一个公认的晚期并发症，水凝胶间隔剂已被用于预防这种不良反应。先前的报道表明，水凝胶间隔物的体积在植入后至少3个月内保持稳定；然而，没有报告早期解决的病例。因此，本研究旨在研究水凝胶间隔剂体积随时间的变化。方法：我们纳入了2020年4月至2022年11月期间在我院接受质子治疗的103例植入水凝胶间隔剂的患者。2例患者因水凝胶垫片放置不当而被排除在前列腺侧德农维利氏筋膜之外。为了检查Space OAR的体积，我们在剂量学治疗计划时使用磁共振成像测量间隔体积，并在剩余的101例患者中再次测量7和21个分数的间隔体积。结果：在101例患者中，4例患者在21个分数时表现出间隔体积显著减少，其中1例患者出现直肠出血。结论：水凝胶间隔物体积的早期意外变化可能从放疗计划开始增加直肠暴露量。临床试验号：不适用。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

BMC Urology UROLOGY & NEPHROLOGY-

CiteScore

3.20

自引率

0.00%

发文量

177

审稿时长

>12 weeks

期刊介绍： BMC Urology is an open access journal publishing original peer-reviewed research articles in all aspects of the prevention, diagnosis and management of urological disorders, as well as related molecular genetics, pathophysiology, and epidemiology. The journal considers manuscripts in the following broad subject-specific sections of urology: Endourology and technology Epidemiology and health outcomes Pediatric urology Pre-clinical and basic research Reconstructive urology Sexual function and fertility Urological imaging Urological oncology Voiding dysfunction Case reports.