@misc{oai:repo.qst.go.jp:00081596,
 author = {猪俣, 麻美 and 鈴木, 優維 and 勝間田, 匡 and 中島, 猛雄 and 古市, 渉 and 山岡, 恵士 and 菅, 満喜人 and 山本, 淳史 and 水野, 秀之 and 河野, 良介 and Asami, Inomata and Yui, Suzuki and Masashi, Katsumata and Nakajima, Takeo and Wataru, Furuichi and Keisi, Yamaoka and Makito, Suga and Atsushi, Yamamoto and Hideyuki, Mizuno and Ryosuke, Kohno},
 month = {May},
 note = {[Purpose] In the QST hospital, carbon ion radiotherapy (CIRT) using spot-scanning was started in 2011. In order to check each individual CIRT treatment plan and its treatment delivery, the scanning system and its treatment planning system require dosimetric patient-specific Quality Assurance (PQA) before CIRT. We report results of PQA in half year of 2017.
[Methods] For the PQA, all the planned beams are recalculated on a water phantom with treatment planning software. The recalculated dose distributions are compared with the measured distributions using a 2D ionization chamber array at three depth, including 95% area of prescription dose. These are evaluated using 3%/3 mm gamma criteria with a pass threshold of 90%. We analyzed PQA results for about 1500 shots from September 2017 to March 2018, evaluated the pass rate for 10 disease sites with various target volume, energy and measurement depth.
[Results] The pass rate for prostate, head and neck, and bone and soft tissue were 95.9%, 99.3%, and 91.5%, respectively. 95.9% of lung plans with low energy beam passed. Overall, 95% of the measured beams for all shots passed the gamma criteria, and were consistent with the plan. Although the rest of 5% failed the criteria, there were no dependence of measurements depth and disease sites in these failures.
[Conclusion] The results of the PQA in the second half of FY2017 was analyzed. The overall quality assurance measurement passing rate was 95% for the gamma index criteria of 3%/3 mm. It was obvious that there was no disease sites or target dependency in these pass rates. Therefore, we could ensure the safety of the CIRT treatment plans., 第119回日本医学物理学会学術大会},
 title = {Evaluation of Patient-specific Quality Assurance for Spot-Scanning Carbon Ion Radiotherapy},
 year = {2020}
}