Antitumor effect of combination with intra-arterial infusion of hydrogen peroxide and radiotherapy

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K17135
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 52040:Radiological sciences-related
• Research Institution: Shiga University of Medical Science
• Principal Investigator: Tomozawa Yuki 滋賀医科大学, 医学部, 助教 (90585689)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: KORTUC / オキシドール / VX2腫瘍 / 動注

Outline of Final Research Achievements

We evaluated the anti-tumor effect of the combination of intra-arterial infusion of hydrogen peroxide and radiotherapy. Twenty Japanese white rabbits were randomly assigned to four equal groups two weeks after VX2 tumor transplantation to the left hind-limb. We then performed the treatment in the according ways; RT (radiotherapy only), KT (local injection of hydrogen peroxide and radiotherapy), KTA (intra-arterial infusion of hydrogen peroxide and radiotherapy), and NT (No treatment) groups. The anti-tumor effects were assessed by the tumor growth rates. The tumor size increased by 136 ± 43% in RT group, 81 ± 75% in KT group, 117 ± 39% in KTA group, 642 ± 230% in NT group, respectively. Although there were no statistically significant differences among the treatment groups, the tumor growth rates in KT group and KTA group were lower than that in RT group. Intra-arterial infusion of hydrogen peroxide can make VX2 tumor more sensitive to radiotherapy.

Free Research Field

放射線医学

Academic Significance and Societal Importance of the Research Achievements

血管内治療の技術を用いることで、カテーテルを腫瘍の栄養動脈内まで挿入し、放射線増感剤であるオキシドールを経カテーテル的に動脈内注入することができ、直接穿刺が困難な深部に位置する腫瘍に対しても放射線治療の効果をある程度増強できる可能性が示唆された。今後は手技として既に確立されている動注リザーバー留置術と組み合わせて、様々な部位の腫瘍に応用可能となることが期待される。
ただし直接穿刺によるオキシドールの局所注入と比較すると、動注による増感作用は弱く、動注するオキシドールの量や濃度についての検討や、バルーンカテーテルを用いて血流を閉塞しオキシドールを腫瘍内に停滞させる等投与法の工夫が必要である。