Establishment of new selection system for adjuvant chemotherapy of colorectal cancer

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K09011
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 55020:Digestive surgery-related
• Research Institution: Kyushu University
• Principal Investigator: OKI Eiji 九州大学, 大学院医学研究院, 准教授 (70380392)
• Co-Investigator(Kenkyū-buntansha): 北尾 洋之 九州大学, 薬学研究院, 教授 (30368617)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: ゲノム検査 / 遺伝子検査 / 遺伝子サブタイプ / ctDNA / 大腸癌 / 術後補助療法

Outline of Final Research Achievements

Collaborated with other universities and companies to develop a genetic diagnosis system for the purpose of determining postoperative treatment strategy through genome testing. In collaboration with Sysmex, we developed a new postoperative prognostic system using budding signature, and confirmed in clinical cases that budding signature can be used to predict the prognosis of cancer. In collaboration with Natera, we conducted a prospective observational study of postoperative colorectal cancer cases using ctDNA. In this ctDNA assay, whole exome sequencing (WES) is performed on surgical specimens, and a custom panel of 16 gene sets is selected for each case, taking tumor-specific single nucleotide substitution variants (SNVs) into account. We found thata positive circulating tumor DNA in the blood at 4 weeks postoperatively was associated with a significantly higher risk of recurrence compared with negative results.

Free Research Field

消化器外科学

Academic Significance and Societal Importance of the Research Achievements

大腸癌は切除可能であっても、3割程度の患者が術後に再発する。本検討により、これら遺伝子検査が、腫瘍マーカーや画像検査と比較して鋭敏、迅速に術後の再発予測ができることが明らかとなった。これら方法を使い、再発しにくい患者、再発しやすい患者を層別化し、術後の治療を省略する、もしくは強力な術後治療を行うことができる。結果的に大腸癌の予後が飛躍的に改善することが期待される。