A preliminary study on rectal dose reduction associated with hyaluronic acid implantation in brachytherapy for prostate cancer

作     者：Tairo Kashihara Yuka Urago Hiroyuki Okamoto Mihiro Takemori Hiroki Nakayama Shohei Mikasa Tetsu Nakaichi Kotaro Iijima Takahito Chiba Junichi Kuwahara Satoshi Nakamura Weishan Chang Yoshiyuki Matsui Hiroshi Igaki 

作者机构：Department of Radiation OncologyNational Cancer Center Hospital5-1-1 TsukijiChuo-kuTokyoJapan Radiation Safety and Quality Assurance DivisionNational Cancer Center Hospital5-1-1 TsukijiChuo-kuTokyoJapan Department of Radiological SciencesGraduate School of Human Health SciencesTokyo Metropolitan University7-2-10 Higashi-OguArakawa-kuTokyoJapan Department of Radiological TechnologyNational Cancer Center Hospital5-1-1 TsukijiChuo-kuTokyoJapan Department of Urological OncologyNational Cancer Center Hospital5-1-1 TsukijiChuo-kuTokyoJapan 

出 版 物：《Asian Journal of Urology》 (亚洲泌尿外科杂志（英文）)

年 卷 期：2024年第11卷第2期

页      面：286-293页

核心收录：

学科分类：1002[医学-临床医学] 100214[医学-肿瘤学] 10[医学] 

基　　金：Foundation for the Promotion of Cancer Research in Japan HekaBio AstraZeneca 

主　　题：Brachytherapy Hyaluronicacid Hydrogel Prostaticneoplasm Radiotherapy 

摘      要：Objectives: Hydrogel spacer (HS) was developed to reduce rectal toxicities caused by radiotherapy, but has been reported to cause major adverse events. Our institute has attempted to introduce a hyaluronic acid (HA) as an alternative spacer. This study aimed to compare rectal doses and geometric distributions between the HS and HA implantation in prostate cancer.Methods: HS and HA were inserted in 20 and 18 patients undergoing high-dose brachytherapy, respectively. The rectum spacer volumes injected were 10 mL and 22 mL, respectively. In the treatment planning system, 13.5 Gy was administered with common catheter positions. The rectal dose indices were assessed between the spacer groups for dosimetry evaluation. Distances between the prostate and rectum and configurations of the spacers were compared.Results: The mean doses irradiated to 0.1 and 2 mL of the rectum were 10.45 Gy and 6.71 Gy for HS, and 6.73 Gy and 4.90 Gy for HA (p0.001). The mean minimum distances between the prostate and rectum were 1.23 cm and 1.79 cm for HS and HA, respectively (p0.05). Geometrical configuration comparisons revealed that HA has a higher ability to expand the space than HS.Conclusion: The rectal dose reduction ability of HA is significantly greater than that of HS, suggesting its potential as a new spacer.