Analysis of tumor reoxygenation by percutaneous CO2 therapy using FMISO-PET

2020 Fiscal Year Final Research Report

• Project/Area Number: 18K15547
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 52040:Radiological sciences-related
• Research Institution: Kobe University
• Principal Investigator: Maruyama Koji 神戸大学, 医学研究科, 医学研究員 (40815990)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: 二酸化炭素 / 腫瘍内低酸素 / 生体内 / LM8腫瘍 / 18F-FMISO PET-CT

Outline of Final Research Achievements

Carbon dioxide (CO2) treatment is reported to have an antitumor effect owing to the improvement in intratumoral hypoxia. Previous studies were based on histological analysis alone. In this study, the improvement in intratumoral hypoxia by percutaneous CO2 treatment was evaluated in vivo using 18F-fluoromisonidazole (FMISO) PET-CT images. 18F-FMISO tumor uptake was quantitatively evaluated between the CO2-treated group and a control group (air administration). The tumor volume was not significantly different between the two groups. The maximum standardized uptake value (SUVmax), tumor-to-liver ratio (TLR), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were significantly lower in the CO2-treated group than in the control group. To conclude, 18F-FMISO PET revealed that percutaneous CO2 treatment improved intratumoral hypoxia in vivo. This technique enables assessment of the therapeutic effect in CO2 treatment by imaging, and may contribute to its clinical application.

Free Research Field

放射線医学

Academic Significance and Societal Importance of the Research Achievements

炭酸ガス療法の抗腫瘍効果および化学療法、放射線治療の増感作用を立証されてきたが、低酸素改善については病理組織学的な検証しかなされておらず、治療の臨床応用や本体解明において、画像診断などの生体検査による評価が必須と考えられた。本研究により、18F-FMISO PETを用いることで経皮的炭酸ガス療法による腫瘍内の低酸素状態改善を生体内で確認可能であることが証明され、炭酸ガス療法の臨床応用に寄与すると考える。