The effect of immune-checkpoint pathway on the prognosis in head and neck cancer treated with radiotherapy

2021 Fiscal Year Final Research Report

• Project/Area Number: 17K10468
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Radiation science
• Research Institution: Jichi Medical University
• Principal Investigator: Shirai Katsuyuki 自治医科大学, 医学部, 教授 (10400748)
• Project Period (FY): 2017-04-01 – 2022-03-31
• Keywords: PD-L1 / PD-1 / 免疫チェックポイント阻害剤 / 頭頸部腫瘍 / 扁平上皮癌 / 食道癌

Outline of Final Research Achievements

Radiotherapy plays a major role in head and neck cancer. However, there are many cases of recurrence in advanced disease; therefore, prognostic predictors are warranted to determine the treatment strategy. Recently, the molecular mechanism of immune checkpoints has been reported as a possible mechanism of tumor progression and resistance to treatment. In this study, we investigated protein expression of immune checkpoint molecular mechanisms and their prognostic significance in patients treated with radiotherapy (photon and carbon-ion radiotherapy) at Gunma University. First, clinical outcomes of head and neck tumors treated with radiotherapy (x-ray and heavy particle therapy) were analyzed. However, in 2017, I moved from Gunma University to Jichi Medical University, making it difficult to continue the study. Therefore, I reported the research results, focusing on clinical outcomes for head and neck cancer.

Free Research Field

放射線腫瘍学

Academic Significance and Societal Importance of the Research Achievements

頭頸部癌において根治的治療は手術療法であるが、発声や嚥下などの頭頸部領域の機能温存を考慮した場合、放射線治療の役割は大きい。放射線治療においてはIMRTや重粒子線治療などの高精度化に伴い、治療成績の改善が認められる。しかし進行癌ではいまだ再発をきたす症例も多く、免疫染色を含めた治療成績予測因子についての探索は重要となる。近年、腫瘍の進行や治療抵抗性のメガニズムとして免疫チェックポイン ト分子機構が注目されている。頭頸部腫瘍に対する放射線治療の予後予測因子や、臨床成績、有害事象の解析や発表は重要であり、将来的な治療成績の改善の一助となり、ひいては社会貢献に結びつくと考える。