Annual Report 2024

Department of Radiation Oncology

Sadamoto Zenda, Masaki Nakamura, Hidenari Hirata, Hidehiro Hojo

Introduction

 Radiotherapy (RT) plays an essential role in the management of cancer patients. It is used as a curative treatment for many patients with locoregional localized malignant disease, integrated therapy combined with chemotherapy and/or surgery and as a palliative treatment for patients for whom curative treatment is not an option.

 In radiotherapeutic approaches, the radiation dose to the loco-regional tumor must be as high as possible, while the dose to the surrounding normal tissues should be kept as low as possible to maintain the severity of radiation related complications within an acceptable level.

 The primary aim of the Department of Radiation Oncology is to develop high precision RT such as intensity-modulated radiation therapy (IMRT), image-guided radiation therapy (IGRT), stereotactic body radiotherapy (SBRT), and proton beam therapy (PBT), and to establish the definitive role of RT in cancer treatment. Another important goal is to establish standard treatments for various types of cancer and optimal irradiation techniques including total dose, fractionation, and radiation fields.

The Team and What We Do

 At present, the staff of the Department of Radiation Oncology consists of 5 physicians (radiation oncologists), 27 radiation technologists, and 5 medical physicists. We have more than 1,500 new cases of RT and more than 300 new patients for PBT every year.

 Quality assurance of RT and PBT is performed by medical physicists and radiation technologists.

 The selection of treatment approach is determined through clinical conference which consists of surgeon, medical oncologists and radiation oncologists.

 As for the details of RT, we check all patients who receive RT/PBT in daily morning conference.

 Recently we have accepted not only Japanese patients but also Asian patients, and the number of Asian patients has been increasing.

Research Activities

 Head and neck cancer

1) Establishment of optimal combined approaches including proton beam therapy for skull base tumors

2) Establishment of optimal combined approaches including photon beam therapy and chemotherapy for locally advanced head and neck cancer

3) Palliative radiotherapy for elderly head and neck patients

 Lung cancer

1) Proton Beam Therapy (PBT) for lung cancer

2) Search for biomarkers to predict lung cancer recurrence after radiotherapy

 Breast cancer

1) Hypo-fractionated RT for elderly patients

2) Use of IMRT to avoid late toxicity

 Liver cancer

1) Proton Beam Therapy (PBT) for hepatocellular carcinoma (HCC)

2) Stereotactic body radiotherapy (SBRT) for hepatocellular carcinoma (HCC)

3) Proton Beam Therapy (PBT) for liver metastases

 Prostate cancer

1) IMRT or PBT for prostate cancer

2) PBT for foreign patients with prostate cancer

Clinical Trials

1) JCOG1912

2) iProton study

3) JCOG 1315C

4) JCOG1408

5) JROSG17-4

6) JROSG19-1

7) P-SBRT

8) JCOG1807C

9) JCOG2108

10) JCOG1408A1

11) JCOG2110

12) JCOG1806

13) HyPORT-BC

14) JCOG2211

15) Hemostop

16) JCOG1904

17) JCOG1908E

18) PC001-01

19) JROSG17-5

Future Prospects

 We now aim to establish a system that can provide high-quality and safe high-precision radiation therapy, and we would like to promote the research and development of innovative technologies related to RT, radiation biology and medical physics.

List of papers published in 2024

Journal

1. Yonemura M, Tachibana H, Kojima T, Seki K, Nakaichi T, Rachi T, Tachibana R, Akimoto T. Three-dimensional source position verification in image-guided high-dose-rate brachytherapy using an XCT-based gel dosimeter. Medical physics, 52:1243-1255, 2025

2. Harada T, Tsuji T, Ueno J, Konishi N, Yanagisawa T, HIjikata N, Ishikawa A, Hashimoto K, Kagaya H, Tatematsu N, Zenda S, Kotani D, Kojima T, Fujita T. Clinical mechanism of muscle mass loss during neoadjuvant chemotherapy in older patients with esophageal cancer: a prospective cohort study. Diseases of the esophagus, 38:doae096, 2025

3. Sakai SA, Saeki K, Chi S, Hamaya Y, Du J, Nakamura M, Hojo H, Kojima T, Nakamura Y, Bando H, Kojima M, Suzuki A, Suzuki Y, Akimoto T, Tsuchihara K, Haeno H, Yamashita R, Kageyama SI. Mathematical Modeling Predicts Optimal Immune Checkpoint Inhibitor and Radiotherapy Combinations and Timing of Administration. Cancer immunology research, 13:353-364, 2025

4. Ito Y, Zenke Y, Sakai T, Shibata Y, Izumi H, Nosaki K, Umemura S, Matsumoto S, Yoh K, Nakamura M, Hojo H, Izumo T, Goto K. A simplified scoring system for predicting treatment response in limited-stage small-cell lung cancer (EAST score). Future oncology (London, England), 21:473-481, 2025

5. Hirotaki K, Moriya S, Tomizawa K, Wakabayashi M, Motegi A, Ito M, Sakae T. Prediction and Monitoring of Adaptive Radiation Therapy Timing Using Two-dimensional X-ray Image-based Water Equivalent Thickness. Anticancer research, 45:387-397, 2025

6. Hirose K, Nakanishi Y, Ogasawara RA, Imasato N, Inoue M, Sekiya K, Kataoka M, Hojo H, Yajima S, Zenda S, Masuda H. Risk factors for rectal wall infiltration in hydrogel spacer placement: Influence of biopsy approach. International journal of urology, 32:183-189, 2025

7. Hirotaki K, Tomizawa K, Kitou S, Jinno S, Moriya S, Fujisawa T, Zenda S, Sakae T, Ito M. Dosimetric Comparison of Noncoplanar VMAT Without Rotating the Patient Couch Versus Conventional Coplanar/Noncoplanar VMAT for Head and Neck Cancer: First Report of Dynamic Swing Arc. Advances in radiation oncology, 10:101706, 2025

8. Bando H, Kumagai S, Kotani D, Mishima S, Irie T, Itahashi K, Tanaka Y, Habu T, Fukaya S, Kondo M, Tsushima T, Hara H, Kadowaki S, Kato K, Chin K, Yamaguchi K, Kageyama SI, Hojo H, Nakamura M, Tachibana H, Wakabayashi M, Fukui M, Fuse N, Koyama S, Mano H, Nishikawa H, Shitara K, Yoshino T, Kojima T. Atezolizumab following definitive chemoradiotherapy in patients with unresectable locally advanced esophageal squamous cell carcinoma - a multicenter phase 2 trial (EPOC1802). Nature cancer, 6:445-459, 2025

9. Mizumoto M, Terashima K, Makishima H, Suzuki M, Ogino T, Waki T, Iwata H, Tamamura H, Uchinami Y, Akimoto T, Okimoto T, Iizumi T, Murakami M, Katoh N, Maruo K, Shibuya K, Sakurai H. Proton Beam Therapy for Intrahepatic Cholangiocarcinoma: A Multicenter Prospective Registry Study in Japan. Liver cancer, 13:161-168, 2024

10. Habu T, Kumagai S, Bando H, Fujisawa T, Mishima S, Kotani D, Nakamura M, Hojo H, Sakashita S, Kinoshita T, Yano T, Mitsunaga S, Nishikawa H, Koyama S, Kojima T. Definitive chemoradiotherapy induces T-cell-inflamed tumor microenvironment in unresectable locally advanced esophageal squamous cell carcinoma. Journal of gastroenterology, 59:798-811, 2024

11. Ogawa K, Ishikawa H, Toyozumi T, Noma K, Kono K, Hojo H, Tamamura H, Azami Y, Ishida T, Nabeya Y, Iwata H, Araya M, Tokumaru S, Maruo K, Oda T, Matsubara H. Comparison of proton-based definitive chemoradiotherapy and surgery-based therapy for esophageal squamous cell carcinoma: a multi-center retrospective Japanese cohort study. Esophagus, 21:484-494, 2024

12. Harada H, Suefuji H, Mori K, Ishikawa H, Nakamura M, Tokumaru S, Murakami M, Ogino T, Iwata H, Tatebe H, Kubo N, Waki T, Yoshida D, Nakamura M, Hashimoto T, Araya M, Nakajima M, Nakayama H, Satouchi M, Shioyama Y. Proton and carbon ion radiotherapy for operable early-stage lung cancer; a prospective nationwide registry. Radiotherapy and oncology, 198:110385, 2024

13. Ishibashi N, Ejima Y, Soejima T, Kawaguchi H, Taguchi S, Ito H, Shimizuguchi T, Isobe K, Hasegawa M, Sasai K, Imai M, Shimoda E, Kaizu H, Okano N, Imagumbai T, Akimoto T. Autologous Peripheral Blood Stem Cell Transplantation and Timing of Local Radiation Therapy in Patients With Malignant Lymphoma: Results of the Japanese Radiation Oncology Study Group Questionnaire Survey. Anticancer research, 44:3033-3041, 2024

14. Sato M, Enokida T, Fujisawa T, Okano S, Takeshita N, Tanaka N, Tanaka H, Motegi A, Zenda S, Shinozaki T, Matsuura K, Hayashi R, Akimoto T, Tahara M. Induction chemotherapy with paclitaxel, carboplatin, and cetuximab (PCE) followed by chemoradiotherapy for unresectable locoregional recurrence after curative surgery in patients with squamous cell carcinoma of the head and neck. Frontiers in oncology, 14:1420860, 2024

15. Uezono H, Onoe T, Shikama N, Ono Y, Hirata H, Ito Y, Yasuda K, Imano N, Kikuchi K, Kashihara T, Kawamoto T, Nakamura N. Uptake of ultra-hypofractionated radiation therapy following breast-conserving surgery among patients with early-stage breast cancer: a multi-institutional questionnaire survey. Breast cancer (Tokyo, Japan), 31:1071-1079, 2024

16. Harada T, Tsuji T, Fukushima T, Ikeda T, Toyama S, Konishi N, Nakajima H, Suzuki K, Matsumori K, Yanagisawa T, Hashimoto K, Kagaya H, Zenda S, Kojima T, Fujita T, Ueno J, Hijikata N, Ishikawa A, Hayashi R. The implementation status of prehabilitation during neoadjuvant chemotherapy for patients with locally advanced esophageal cancer: a questionnaire survey to the board-certified facilities in Japan. Esophagus, 21:496-504, 2024

17. Kato H, Kawai K, Nakano D, Dejima A, Ise I, Natsume S, Takao M, Shibata S, Iizuka T, Akimoto T, Tsukada Y, Ito M. Does Colorectal Stenting as a Bridge to Surgery for Obstructive Colorectal Cancer Increase Perineural Invasion? Journal of the anus, rectum and colon, 8:195-203, 2024

18. Nakamura M, Fujisawa T, Oyoshi H, Zhou Y, Fukushi K, Hirata H, Tomizawa K, Motegi A, Hojo H, Wakabayashi M, Kano K, Ohno R, Nakamura A, Yamaguchi M, Zenda S. Acute toxicity of hypofractionated radiotherapy for Japanese breast cancer patients after surgery: a single center prospective observational study (HyPORT-BC). Breast cancer (Tokyo, Japan), 31:1176-1181, 2024

19. Zenda S, Kashihara T, Saito T, Okamoto H, Kadoya N, Chiba T, Noda SE, Kawaguchi T, Jingu K, Shibuya K, Uno T, Igaki H. Two-fractionated stereotactic magnetic resonance-guided adaptive radiation therapy for patients with prostate cancer (SMART PRO trial): protocol for a confirmatory clinical trial. BMJ open, 14:e082899, 2024

20. Motegi A, Kageyama SI, Kashima Y, Hirata H, Hojo H, Nakamura M, Fujisawa T, Enokida T, Tahara M, Matsuura K, Zenda S. Detection of HPV DNA in Saliva of Patients with HPV-Associated Oropharyngeal Cancer Treated with Radiotherapy. Current oncology (Toronto, Ont.), 31:4397-4405, 2024

21. Makita K, Hojo H, Oyoshi H, Fujisawa T, Nakamura M, Uchida G, Koike Y, Zhou Y, Tomizawa K, Fukushi K, Zenda S. High Fracture Risk of Femoral Bone Metastasis Treated with Palliative Radiotherapy in Recent Years. Current oncology (Toronto, Ont.), 31:7437-7444, 2024

22. Harada T, Tsuji T, Ueno J, Konishi N, Yanagisawa T, Hijikata N, Ishikawa A, Hashimoto K, Kagaya H, Tatematsu N, Zenda S, Kotani D, Kojima T, Fujita T. Association of Preoperative Physical Fitness With Post-Esophagectomy Pneumonia in Older With Locally Advanced Esophageal Cancer: An Exploratory Prospective Study. Journal of surgical oncology, 2024

23. Higashino T, Wakabayashi M, Zenda S, Yasunaga Y, Araki J, Mukaigawa T, Onitsuka T, Nakagawa M, Hamahata A, Narita K, Arikawa M, Takanari K, Kadota H, Yanagisawa D, Tanaka K, Matsumoto H, Kimata Y, Miyamoto S, Sakuraba M, Kawai K, Terao Y, Hyodo I, Ishida K, Yoshimura K. Impact of radiotherapy-related late toxicities of skin and soft tissue in the neck on quality of life in head and neck cancer patients: a multi-institutional observational study in Japan. Supportive care in cancer, 33:64, 2024

24. Yasuda K, Kiyota N, Matsuura K, Saito S, Honma Y, Imamura Y, Tanaka K, Zenda S, Onoe T, Kodaira T, Kobayashi S, Aoyama H, Hanai N, Homma A. Indications for chemoradiotherapy in older patients with locally advanced head and neck cancer in Japan: a questionnaire survey in the JCOG head and neck cancer study group. Frontiers in oncology, 14:1441056, 2024