Abstract

In conducting dosimetric assays of seed sources containing iodine-125 (125I), several major guidelines require the medical physicist to verify the source strength before patient treatment. Japanese guidelines do not mandate dosimetric assays at medical facilities, but since 2017, three incidents have occurred in Japan wherein seeds with incorrect strengths were delivered to medical facilities. Therefore, this study aimed to survey the current situation and any barriers to conducting the dosimetric assay of iodine-125 seeds at medical facilities in Japan. We conducted a questionnaire-based survey from December 2020 to April 2021, to examine whether seed assay and verification of the number of seeds delivered were being performed. We found that only 9 facilities (16%) performed seed assay and 28 (52%) verified the number of seeds. None of the facilities used an assay method that ensured traceability. The reasons for not performing an assay were divided into two categories: lack of resources and legal issues. Lack of resources included lack of instruments, lack of knowledge of assay methods, shorthand, or all of the above, whereas legal issues included the inability to resterilize iodine-125 seeds distributed in Japan and/or purchase seeds dedicated to the assay. Dosimetric assays, including simple methods, are effective in detecting calibration date errors and non-radioactive seeds. The study findings suggest that familiarization of medical personnel with these assay methods and investigation of the associated costs of labor and equipment should be recommended, as these measures will lead to medical reimbursement for quality assurance.

Details

Title
Current status and issues with the dosimetric assay of iodine-125 seed sources at medical facilities in Japan: a questionnaire-based survey
Author
Kojima, Toru 1 ; Kawamura, Shinji 2 ; Otani, Yuki 3 ; Hanada, Takashi 4 ; Wakitani, Yuichiro 5 ; Naniwa, Kenta 6 ; Yorozu, Atsunori 7 ; Ikushima, Hitoshi 8 ; Dokiya, Takushi 9 

 Department of Radiation Oncology, Saitama Prefectural Cancer Center , 780 Komuro, Ina-machi, Saitama 362-0806 , Japan 
 Department of Radiological Technology, Graduate School of Health Sciences , Teikyo-Univercity, 6-22 Misaki-machi, Omuta, Fukuoka 836-8505 , Japan 
 Department of Radiology , Kaizuka City Hospital, 3-10-20 Hori, Kaizuka, Osaka 597-0015 , Japan 
 Department of Radiology, Keio University School of Medicine , 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582 , Japan 
 Japan Radioisotope Association , 2-28-45 Hon-komagome, Bunkyo-ku, Tokyo 113-8941 , Japan 
 Chiyoda Technol Corporation , 1-7-12 Yushima, Bunkyo-ku, Tokyo 113-8681 , Japan 
 Department of Radiology, National Hospital Organization Tokyo Medical Center , 2-5-1, Higashigaoka, Meguro-ku, Tokyo 152-8902 , Japan 
 Department of Therapeutic Radiology, Tokushima University Graduate School , 3-18-15 Kuramoto-cho, Tokushima 770-8503 , Japan 
 The Japan Foundation for Prostate Research , 2-9-3 Higashi-Shimbashi, Minato-ku, Tokyo 105-0021 , Japan 
Pages
962-966
Publication year
2023
Publication date
Nov 2023
Publisher
Oxford University Press
ISSN
04493060
e-ISSN
13499157
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
3168369343
Copyright
© The Author(s) 2023. Published by Oxford University Press on behalf of The Japanese Radiation Research Society and Japanese Society for Radiation Oncology. This work is published under https://creativecommons.org/licenses/by-nc/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.