The Significance of ctDNA as a Predictor of Recurrence in Surgical Resection Cases Using Next-Generation Sequencing

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K17764
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 55040:Respiratory surgery-related
• Research Institution: Kindai University
• Principal Investigator: Ohara Shuta 近畿大学, 大学病院, 助教 (20813926)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: circulating tumor DNA / liquid biopsy / reccurence / surgery / lung cancer / Signatera / CAPP-Seq / NSCLC

Outline of Final Research Achievements

In this study, we used CAPP-Seq and Signatera to evaluate the relationship between postoperative prognostic and ctDNA status and recurrence on imaging studies.
In a landmark analysis (median 9 days postoperatively, range 2-53 days), 5 patients tested positive for ctDNA and all recurred, with ctDNA positivity associated with a significantly worse prognosis. Five more patients tested positive for ctDNA during follow-up, and all relapsed. The prognosis was significantly worse if ctDNA was detected at least once during follow-up. Overall, the median lead time for ctDNA-positive imaging was 2.8 (0-12.8) months. ctDNA negativity was associated with a favorable outcome, with a long-term negative predictive value of 83.3% (30/36 patients).

Free Research Field

Thoracic surgery

Academic Significance and Societal Importance of the Research Achievements

腫瘍残存病変を検出するためのcirculating tumor DNA（ctDNA）のモニタリングは、様々ながん種において再発予測や薬物療法の個別化などの面でその有用性が示されている。しかし、非小細胞肺がんにおけるその有効性については、十分なデータはない。本研究ではCAPP-SeqやSignateraを用いて術後の予後予測やctDNAの状態と画像検査における再発の関係を評価し,術後の採血ポイントを術後早期だけでなく、6か月毎におこなうことで、術後の予後予測だけでなく、術後再発の早期発見にctDNA解析が有用であることが示された。