Radiation Oncology

Prof. Yasushi Nagata

【Research Keyword】
High-precision radiotherapy, intensity-modulated radiotherapy, stereotactic body radiotherapy, medical physics, X-ray therapy, particle beam therapy, dosimetry technology, dose simulation technology, irradiation technology, radiation imaging technology, medical physicists

【Recent highlights】
The project aimed to establish an advanced radiotherapy team for supporting regional and Asian undeveloped radiotherapy institutions started in 2016.

The Hiroshima High-Precision Radiotherapy Cancer Center opened near the north entrance of JR Hiroshima Station in October 2015. It offers high-precision advanced radiotherapy with three of the latest radiotherapy devices in a location with convenient transport access. It has network links to four hospitals in the city—Hiroshima City Hiroshima Citizens Hospital, Hiroshima Prefectural Hospital, Hiroshima Red Cross Hospital & Atomic-bomb Survivors Hospital, and Hiroshima University Hospital—that have already developed a framework for patient referrals and human resource secondment from designated regional cancer centers and hospitals in the prefecture, creating a system whereby patients from anywhere in the prefecture can now access radiotherapy best suited to their needs.

In terms of medical physics research, we have received various government research grants. Currently, we are collaborating with a range of research institutions and manufacturers on medical physics research topics that include R&D for a Japanese radiotherapy planning system as well as the world’s first real-time imaging tumor response observation system for dose-volume delivery guided particle therapy.

Profiles of Faculty and Research Scholars

Human resource development is an important task of any university, and we are focusing our efforts on training students and young doctors. This training comprises 19 lectures for third-year medical students in subjects related to radiation oncology, radiation biology, and medical physics. Fourth-year students are assigned roles in medical research, and as part of clinical practice for fifth- and sixth-year students, radiation oncology department takes the central role in providing comprehensive practical training in clinical oncology, which encompasses radiology, chemotherapy, and palliative care.

For clinical residents and young doctors, we provide training based on external beam radiotherapy, including the latest high-precision radiotherapy; interstitial brachytherapy, which is highly effective for localized tumors such as tongue cancer and uterine cancer; and radioisotope therapy and other forms of primary care. In practical terms, they learn about making decisions on care, diagnosis, and treatment strategies; producing a treatment plan; actually treating patients; evaluating responses to radiotherapy; investigating adverse events; and conducting post-treatment follow-up. They give presentations on diagnoses, treatment plans, progress of treatments, problems, and other matters concerning their patients during case conferences in the Department of Radiation Oncology, which both deepens their understanding of the disorders concerned and helps improve their presentation skills. In joint conferences with other clinical departments and cancer boards, they learn about the establishment of treatment strategies by a multidisciplinary team and the procedure for interdisciplinary treatment for the patients concerned, among other matters. They are also obliged to attend study meetings for the presentation and discussion of summaries of English research papers and textbooks; thus, they are supported in their efforts to acquire knowledge that is both universal and up-to-date.

In medical physics research, we integrate knowledge in physics and medicine to carry out research, development, and quality control in the rapidly evolving field of high-precision radiotherapy, enabling us to provide large numbers of patients with safe, high-quality radiotherapy. Our research department is unusual within Japan in that we combine medical physics research with a well-developed teaching staff, and are engaged in research in cutting-edge medical physics by means of industry-academia-government collaboration. Our Master’s course is certified as a medical physicist training course under the Ministry of Education’s Cancer Professional Training Plan and by the Japanese Board for Medical Physicist Qualification. We make the most of this environment to train medical physicists capable not only of research and teaching but also of working successfully in clinical settings. The graduate students in our laboratory study the fundamentals of medical physics and groundbreaking R&D topics with the aim of becoming medical physicists who can be successful at the global level. In terms of other graduate-level training, we also have an international flavor as we are part of the Phoenix Leader Education Program for Renaissance from Radiation Disaster, which includes students from Mongolia, Malaysia, and the Philippines.

he main research topics for our department are the development of new therapeutic technologies for high-precision radiotherapy and the promotion of clinical trials. In terms of new therapeutic technologies, our research includes studies of the use of metal markers to investigate changes in the position of the esophagus by means of four-dimensional computed tomography (4D-CT), with a view toward its application in high-precision radiotherapy for organs such as the esophagus, liver and lungs that are affected by respiratory movements; the addition of chronological elements in the production of target images for planning radiotherapy for lung cancer; and fundamental research on radiotherapy planning using functional images of the lungs and liver. In terms of clinical trials, we are not only active participants in clinical trials undertaken by organizations such as the Japan Clinical Oncology Group (JCOG) and the Japanese Radiation Oncology Study Group (JROSG), but we are also engaged in developing new evidence by acting as the study secretariat for a variety of other clinical trials. Our research in medical physics includes R&D on a Japanese radiotherapy planning system, research on a scintillator detection system for radiation verification, and R&D on a tumor response observation system for dose-volume delivery guided particle therapy.

【Photo explanation】 Group photograph

【Photo explanation】 Conference in progress

【Photo explanation】 Sample image display from the Japan Plug-in based Radiotherapy Planning System (jPRAPs) developed to help plan radiotherapy for cancer