Proton therapy targeting hypoxic cancer

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K19797
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Radiation science
• Research Institution: Hokkaido University
• Principal Investigator: Yasuda Koichi 北海道大学, 大学病院, 特任助教 (00431362)
• Research Collaborator: NAM Jin Min ; Nishikawa Yukiko
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: 低酸素 / 陽子線治療

Outline of Final Research Achievements

We developed a simulation system for spot-scanning proton therapy targeting hypoxic volume in cancer. Intensity-modulated proton therapy (IMPT) plans using spot-scanning proton therapy system were generated in 10 nasopharyngeal carcinoma patients, and the plans were compared with intensity-modulated X-ray therapy (IMXT). The doses of the parotid gland and the oral cavity and the probabilities of complications were lower in IMPT than IMXT. It was shown that spot-scanning proton therapy was more useful than X-ray therapy for targeting tumor hypoxia.

Free Research Field

放射線治療

Academic Significance and Societal Importance of the Research Achievements

スポットスキャニング陽子線治療は臨床における最先端の放射線治療の一種であるが、今回、低酸素癌を標的とした強度変調陽子線治療が実施可能なことをシミュレーションにて示した。陽子線の特性をいかし、治療抵抗性である腫瘍内部の低酸素領域のみに高線量を投与して治療効果を高め、それ以外の治りやすい領域の線量は抑えることで、正常組織障害のリスクを最大限抑えることが可能な治療となりえる。癌の克服とQOLの維持を両立した癌治療の確立のための基礎的な研究成果と考えられる。