@misc{oai:repo.qst.go.jp:00065711, author = {Noda, Koji and 野田 耕司}, month = {Jun}, note = {Heavy-ion beams are very suitable for the treatment of deeply seated cancer because of an excellent physical-dose distribution and high biological effect around the Bragg peak. Heavy-Ion Medical Accelerator in Chiba, HIMAC, therefore, was constructed for the cancer radiotherapy (RT) with heavy-ions. Since 1994, NIRS has conducted the HIMAC facility for both the carbon-ion RT and related studies with heavy-ions. The total number of patients treated as of December 2014 was in excess of 9,000. In 2003, the Japanese government approved the carbon-ion RT with HIMAC as a highly advanced medical technology. Therefore, NIRS proposed a standard carbon-ion RT facility in order to boost the carbon-ion RT. The fruits of this work were realized as a pilot facility in Gunma University, which has been successfully conducted since 2010. Since 2006, on the other hand, NIRS has been engaged in a “new treatment research project” toward a new next generation research. One of the most important purposes is to realize the “adaptive cancer radiotherapy” to accurately treat tumor even with changing both the tumor size and shapes during a treatment period. For the purpose, the phase-controlled rescanning (PCR), based on a fast 3D scanning, has been developed. The new treatment research facility was constructed in NIRS for the clinical study with this technology, which has been successfully conducted since 2011. As the next stage, a compact carbon-ion rotating gantry has been developed in order to realize the intensity modulated carbon-ion RT (IMCT) combined with the 3D scanning, which will bring the more accurate and shorter-course treatments owing to the higher dose concentration. This rotating gantry will be installed to the third room and its commissioning will be started in 2015. We will report 20 years development of heavy-ion RT with HIMAC., The 2015 International Conference on Applications of Nuclear Techniques (CRETE15)}, title = {Twenty-Year Development of Heavy-Ion Radiotherapy Technology with HIMAC}, year = {2015} }