AccScience Publishing / ARNM / Volume 1 / Issue 2 / DOI: 10.36922/arnm.0914
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Advancements and challenges in interstitial brachytherapy using iodine-125 seeds

Liting Xiong1† Yuhan Yang1† Mengyuan Li1 Ping Jiang1* Chunxiao Li1* Junjie Wang1*
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1 Department of Radiation Oncology, Peking University Third Hospital, Institute of Medical Technology, Peking University Health Science Center, Beijing, China
Submitted: 6 May 2023 | Accepted: 21 August 2023 | Published: 3 October 2023
© 2023 by the Author(s). This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution 4.0 International License ( )

Radiation therapy has been used for over a century in the treatment of tumors, with interstitial tissue treatment using radioactive seeds playing a key role in this approach. Iodine-125 (I-125) seeds are the most commonly used radioactive sealed source for permanent interstitial brachytherapy. In recent decades, significant advancements have been made in the field of interstitial radiation therapy. The development of three-dimensional (3D)-printed personalized templates, treatment planning systems, and robot-assisted systems have significantly improved the accuracy of I-125 brachytherapy. This review summarizes the advances in technology, radiobiology, physics, and immunology of I-125 brachytherapy. These advancements have improved the accuracy of dose delivery and increased the effectiveness of I-125 interstitial brachytherapy. In particular, the utilization of 3D-printed personalized templates has allowed for customized treatment planning and more precise dose delivery. Robot-assisted systems have also made significant contributions by assisting in the precise placement of radioactive seeds during treatment. However, several challenges persist within the field of interstitial I-125 brachytherapy. One of the current issues is the difficulty in accurately predicting the biological response to radiation therapy in individual patients. Addressing this challenge represents an important area for further research, as it has the potential to improve treatment outcomes and minimize side effects. In addition, there is a need for more research into the utilization of immunotherapy in conjunction with interstitial brachytherapy, as this combination has demonstrated promise in preclinical studies. Overall, this review provides a comprehensive overview of the advances and challenges associated with interstitial brachytherapy using I-125 seeds. These advancements offer a theoretical basis for achieving precise and remote medical care in brachytherapy. As technology continues to evolve, it is likely that interstitial brachytherapy will emerge as an even more effective treatment option for cancer patients.

National Natural Science Foundation of China
Natural Science Foundation of Beijing Municipality
Intramural funding from the Beijing University Third Hospital
Special Fund of the National Clinical Key Specialty Construction Program, P. R. China
Cancer Precision Radiotherapy Spark Program of China International Medical Foundation
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Conflict of interest
The authors declare no potential conflicts of interest.
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