Department of Radiological Technology (Radiological Oncology)

Hiroshi Tanizaki, Kanyu Ihara, Tomonori Goka, Ako Aikawa, Toshimitsu Sofue, Miyuki Murata, Yoshihiro Shibata, Yusuke Watanabe, Tatsuya Sakasai, Junichi Kuwahara, Mitsuhiro Kon, Takayuki Mori, Yuusuke Miyamoto, YuutoTanaka, Masataka Ueda, Midori Nonaka, Yusaku Kasai, Yasunori Shuto, Ruka Hata, Kaho Miyagi, Aya Shimoike, Yuka Kondo, Takuma Hanzawa, Koshin Arai, Masashi Kawamura, Homare Murata, Natsuki Furutate, Amane Hashimoto, Shuichirou Kawano, Hiroko Sugaya

Introduction

The Radiological Oncology unit in Department of Radiological Technology is home to four linear accelerators, a CyberKnife, an MRI-guided radiotherapy system (MRIdian), and image-guided radiation therapy (IGRT) and image-guided brachytherapy (IGBT) systems, which we use to provide various radiotherapy treatments, including intensity modulated radiation therapy (IMRT), stereotactic radiation therapy (SRT), and high-dose-rate brachytherapy with IGBT.

The Team and What We Do

1. We performed 2,064 cases of external beam radiotherapy, including 904 cases of volumetric modulated arc radiotherapy (VMAT) and 432 cases of stereotactic radiotherapy (SRT). The number of high-precision radiotherapy cases accounted for approximately 70% of all cases in FY2022.
2. The cobalt MRIdian system has had upgraded to a linear accelerator system in July 2022. Radiotherapy applied with the MRIdian system was performed in 112 cases. A total of 349 sessions of online adaptive treatment were performed.
3. A total of 164 cases were performed with stereotactic irradiation using a CyberKnife, consisting of 151 head-and-neck regions and 13 trunk cases.
4. Total-body irradiation for bone marrow transplantation was performed in 54 cases.
5. Interstitial brachytherapy using a 106-Ru source was performed in 12 cases.
6. High-dose-rate brachytherapy system was updated in August 2022. In-room CT for the image-guided brachytherapy system was upgraded to a large-bore 80-row multi-detector CT scanner, allowing planning with rapid acquisition time and high-quality images.

Research Activities

We have developed a video display system for the respiratory motion management of patients during radiation treatment with the MRIdian system.

Clinical trials

We completed a Phase I clinical trial of Boron Neutron Capture Therapy (BNCT) and initiated a Phase II clinical trial in three patients.

Education

1. We had job rotations among modalities corresponding to our educational programs.
2. One of the radiological technologists belonging to the radiotherapy team was concurrently appointed to the Section of Radiation Safety and Quality Assurance to learn about radiotherapy planning and quality control.
3. We reviewed and improved our workflow through comprehensive training about the processes of radiotherapy.
4. We performed review and organization of the curriculum of the residency program for radiological technologists with specialized knowledge and skills, which will begin accepting residents in FY2022.

List of papers published in 2022

Journal

1. Nakayama H, Okamoto H, Nakamura S, Iijima K, Chiba T, Takemori M, Nakaichi T, Mikasa S, Fujii K, Sakasai T, Kuwahara J, Miura Y, Fujiyama D, Tsunoda Y, Hanzawa T, Igaki H, Chang W. Film measurement and analytical approach for assessing treatment accuracy and latency in a magnetic resonance-guided radiotherapy system. J Appl Clin Med Phys. 2023 19:e13915.
2. Nakaichi T, Okamoto H, Kon M, Takaso K, Aikawa A, Nakamura S, Ijima K, Chiba T, Nakayama H, Takemori M, Mikasa S, Fujii K, Urago Y, Goka T, Shimizu Y, Igaki H. Commissioning and performance evaluation of commercially available mobile imager for image guided total body irradiation. J Appl Clin Med Phys. 2022 26:e13865.
3. Takemori M, Nakamura S, Sofue T, Ito M, Goka T, Miura Y, Iijima K, Chiba T, Nakayama H, Nakaichi T, Mikasa S, Takano Y, Kon M, Shuto Y, Urago Y, Nishitani M, Kashihara T, Takahashi K, Murakami N, Nishio T, Okamoto H, Chang W, Igaki H. Failure modes and effects analysis study for accelerator-based Boron Neutron Capture Therapy. Med Phys. 2023 50(1):424-439.
4. Nishioka S, Okamoto H, Chiba T, Sakasai T, Okuma K, Kuwahara J, Fujiyama D, Nakamura S, Iijima K, Nakayama H, Takemori M, Tsunoda Y, Kaga K, Igaki H. Identifying risk characteristics using failure mode and effect analysis for risk management in online magnetic resonance-guided adaptive radiation therapy. Phys Imaging Radiat Oncol. 2022 6;23時1分-7.
5. Okamoto H, Igaki H, Chiba T, Shibuya K, Sakasai T, Jingu K, Inaba K, Kuroda K, Aoki S, Tatsumi D, Nakamura M, Kadoya N, Furuyama Y, Kumazaki Y, Tohyama N, Tsuneda M, Nishioka S, Itami J, Onishi H, Shigematsu N, Uno T. Practical guidelines of online MR-guided adaptive radiotherapy. J Radiat Res. 2022 21;63(5):730-740.
6. Nakayama H, Okamoto H, Nakamura S, Iijima K, Chiba T, Takemori M, Nakaichi T, Mikasa S, Fujii K, Sakasai T, Kuwahara J, Miura Y, Fujiyama D, Tsunoda Y, Hanzawa T, Igaki H, Chang W. Film measurement and analytical approach for assessing treatment accuracy and latency in a magnetic resonance-guided radiotherapy system. J Appl Clin Med Phys. 2023 19:e13915.