A study on the correlation between the therapeutic effect of BNCT and BPA-PET for head and neck cancer.

2020 Fiscal Year Final Research Report

• Project/Area Number: 18K09312
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 56050:Otorhinolaryngology-related
• Research Institution: Osaka Medical College
• Principal Investigator: Aihara Teruhito 大阪医科大学, 医学部, 特別職務担当教員(専門教授) (30268619)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: BNCT / 頭頸部癌 / ホウ素中性子捕捉療法 / 18FBPA-PET / 中性子束 / N/C比

Outline of Final Research Achievements

PURPOSE: Boron Neutron Capture Therapy (BNCT) is a form of radiation therapy that utilizes alpha rays from thermal neutron capture of the boron atom. We examined whether the items of 1. BPA-PET, 2. DVH, and 3. nuclear cell (N/C) ratio would be the predictors of therapeutic effect.　As a result，1. The 18FBPA-PET study showed tumors with the lowest T/N ratio in GTV at 2.3 or higher were almost CR. 2. We analyzed DVH for our cases. Many non-effective cases fall below 20 Gy-Eq compared to the effective case. 3. The histopathological image of each cases were delineated by computer software, and the N/C ratio was calculated and the N/C ratio divided by the mean dose. We performed statistical analysis of the values for CR and non-CR groups. As a result, statistical significance was recognized.
We consider these three items as predictors of therapeutic effect, and our preliminary results demonstrated that BNCT is a potentially curative therapy for patients with head and neck cancer.

Free Research Field

頭頸部癌，放射線治療

Academic Significance and Societal Importance of the Research Achievements

2020年3月に加速器中性子源が医療機器承認され，同年6月から「切除不能進行頭頸部癌，または再発頭頸部癌」において，保険治療が開始された．BNCTは治療前に抗腫瘍効果が予測可能な数少ない治療法であるが，その予測因子の検討は非常に不確実なものであった．今回の我々が出した結果は，18FBPA-PET，腫瘍中性子束線量，腫瘍組織のT/N比はBNCTの治療効果予測因子になり得る可能性があり，今後頭頸部癌治療の個別化を検討する中で，BNCT治療が選択される可能性を高めた結果だと考えられる．