Elucidation for recurrent mechanism in rectal cancer patients after CRT.

• Project/Area Number: 16K10532
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Digestive surgery
• Research Institution: Mie University
• Principal Investigator: Saigusa Susumu 三重大学, 医学系研究科, リサーチアソシエイト (10632383)
• Co-Investigator(Kenkyū-buntansha): 問山 裕二 三重大学, 医学部附属病院, 准教授 (00422824) ; 田中 光司 三重大学, 医学系研究科, 客員准教授 (10345986) ; 楠 正人 三重大学, 医学系研究科, 教授 (50192026)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Project Status: Completed (Fiscal Year 2018)
• Budget Amount: ¥4,420,000 (Direct Cost: ¥3,400,000、Indirect Cost: ¥1,020,000); Fiscal Year 2018: ¥260,000 (Direct Cost: ¥200,000、Indirect Cost: ¥60,000); Fiscal Year 2017: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000); Fiscal Year 2016: ¥2,340,000 (Direct Cost: ¥1,800,000、Indirect Cost: ¥540,000)
• Keywords: 直腸癌 / 間質 / バイオマーカー / 術前化学放射線療法 / 再発マーカー / 化学放射線療法 / 再発 / 予後 / 癌間質 / 放射線化学療法 / 治療抵抗性

Outline of Final Research Achievements

Immunohistochemical analysis showed that elevated PD-L1 expression in rectal cancer tissues was significantly correlated with presence of lymphovascular invasion and recurrence after curative surgery. Survival curve analysis demonstrated that elevated PD-L1 expression was significantly correlated with poor overall and disease-free survival in rectal cancer patients receiving chemoradiotherapy. Furthermore, number of CD8+ tumor infiltrative lymphocytes (TILs) was positively correlated with FOXP3+ TILs, and CD8+ TILs was significantly increased in patients with high PD-L1 expression.

Academic Significance and Societal Importance of the Research Achievements

本研究結果を用いることで、直腸癌化学放射線療法におけるあらたな予後マーカーとなるほか、免疫チェックポイント阻害剤併用の可能性が考慮された。

Research Products

• [Journal Article] Clinical Implications of Pretreatment: Lymphocyte-to-Monocyte Ratio in Patients With Rectal Cancer Receiving Preoperative Chemoradiotherapy. (2019)
  • Author(s): Yamamoto A, Toiyama Y, Okugawa Y, Oki S, Ide S, Saigusa S, Araki T, Kusunoki M.
  • Journal Title: Dis Colon Rectum. Volume: 62(2) Issue: 2 Pages: 171-180
  • DOI: 10.1097/dcr.0000000000001245
  • Peer Reviewed
• [Journal Article] Identification of Predictors of Recurrence in Patients with Lower Rectal Cancer Undergoing Neoadjuvant Chemotherapy: A Direct Comparison of Short-Course and Long-Course Chemoradiotherapy. (2019)
  • Author(s): Yamamoto A, Toiyama Y, Okugawa Y, Saigusa S, Ide S, Fujikawa H, Hiro J, Yasuda H, Yoshiyama S, Ohi M, Araki T, Kusunoki M.
  • Journal Title: Oncology. Volume: 96(2) Issue: 2 Pages: 70-78
  • DOI: 10.1159/000492617
  • Peer Reviewed
• [Journal Article] Clinical Significance of C-Reactive Protein-to-Albumin Ratio with Rectal Cancer Patient Undergoing Chemoradiotherapy Followed by Surgery (2017)
  • Author(s): Ide S, Toiyama Y, Okugawa Y, Oki S, Yasuda H, Fujikawa H, Yoshiyama S, Hiro J, Kobayashi M, Ohi M, Araki T, Kusunoki M.
  • Journal Title: Anticancer Res. Volume: 37 Pages: 5797-5804
  • Peer Reviewed
• [Presentation] 直腸癌術前化学放射線療法後癌間質変化と臨床病理学因子との関連 (2017)
  • Author(s): 三枝 晋
  • Organizer: 第117回日本外科学会定期学術集会
  • Place of Presentation: パシフィコ（神奈川県・横浜市）