The impact of neoadjuvant chemotherapy for immune microenviroment of rectal cancer

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K16300
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 50010:Tumor biology-related
• Research Institution: Nagoya University
• Principal Investigator: Ogura Atsushi 名古屋大学, 医学部附属病院, 助教 (20867262)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: 術前化学療法 / 免疫微小環境 / CD8 / PD1 / 直腸癌

Outline of Final Research Achievements

The aim of this study is to clarify the relationship between neoadjuvant chemotherapy (NAC) and tumor microenvironment in locally advanced rectal cancer. In 66 patients who underwent curative surgery followed by NAC, NAC significantly increased the patients with PD-1+ (p = 0.016) and CD8+ (p = 0.005). Furthermore, tPD-1+ and tCD8+ before NAC was independent predictive factor for good responder NAC (OR: 29.8, 95% CI: 3.16-281.0, p = 0.003). In the treatment of colorectal cancer, this study would indicate that NAC can stimulate the immunogenesis and tPD-1+ and tCD8+ on biopsy would be a positive predictor for good responders to NAC.

Free Research Field

直腸癌

Academic Significance and Societal Importance of the Research Achievements

本研究により、直腸癌に対するNACの新たな役割と効果予測の免疫学的背景の可能性が示唆された。Nonoperative managementを企図して術前治療がさらに強化されたtotal neoadjuvant therapy（TNT)が拡まる中、治療戦略の安全性と有効性を向上するために治療開始前に奏効予測が立てられることは大きな利点となり得る。特にchemotherapy 1stのTNTにおいては、安全なNOMへの一助とともに、効果不良例への化学放射線療法追加の一助ともなり得る。