2026-11-02 国立がん研究センター
国立がん研究センターの研究グループは、大腸がんの肝転移・肺転移などを手術で切除した患者について、2種類のリキッドバイオプシーを組み合わせることで、術後の再発リスクをより精密に評価できることを示した。前向き多施設共同研究「PRECISION試験」では、118人を対象に、術前の血液から循環腫瘍DNA（ctDNA）を解析する遺伝子プロファイル（CGP）検査と、術後4週の分子的残存病変（MRD）検査を実施した。その結果、術前に予後不良の遺伝子変異プロファイルがあり、術後もMRD陽性だった患者は、両方とも認めない患者と比較して、無再発生存期間に関する再発リスクが約13倍高かった。2つの検査を組み合わせることで、単独検査よりも詳細なリスク層別化が可能となり、術後薬物療法の個別化に役立つ可能性がある。ただし、症例数が限られ、ランダム化比較試験ではない観察研究であるため、結果の検証が必要である。
図1 PRECISION試験の試験デザイン
＜関連情報＞
切除可能な大腸癌オリゴ転移における、循環腫瘍DNAに基づく治療前ゲノムプロファイルと術後分子残存病変検出によるリスク層別化：PRECISION、前向き多施設共同研究
Risk stratification by circulating tumor DNA-based pretreatment genomic profile and post-operative molecular residual disease detection in resectable colorectal oligometastases: PRECISION, a prospective multicenter study
S. Kobayashi ∙ T. Takamoto ∙ A. Shiomi ∙ … ∙ M. Wakabayashi ∙ T. Yoshino ∙ Y. Nakamura
ESMO Open Published:October 28, 2026
DOI:https://doi.org/10.1016/j.esmoop.2026.108622
Highlights
•In a prospective multicenter study, patients with previously untreated resectable colorectal oligometastases were included.
•CGP and postoperative MRD in ctDNA were analyzed.
•Patients with pretreatment poor genomic profiles and postoperative MRD had the worst prognosis.
•Combining pretreatment CGP and postoperative MRD in ctDNA showed potential for improved prognostic stratification.
Abstract
Background
The role of a comprehensive genomic profile (CGP) and molecular residual disease (MRD) in circulating tumor DNA (ctDNA) for risk stratification of resectable colorectal oligometastases (CRMs) remains unclear. This study aimed to investigate the feasibility of ctDNA analysis in patients with CRM and to conduct an exploratory assessment of its recurrence risk.
Patients and methods
This study assessed ctDNA in patients with previously untreated resectable CRM scheduled for curative resection, before starting treatment and 4 weeks postoperatively. Pretreatment samples were prospectively tested for genomic alteration using a 74-gene CGP assay (Guardant360). The pathogenic mutations in BRAF, KRAS, PIK3CA, SMAD4, or TP53 were defined as poor genomic profiles. Postoperative samples were retrospectively analyzed for MRD using a methylation-based MRD assay (Guardant Reveal).
Results
Among 118 eligible patients, pretreatment ctDNA was detected in 114 (96.6%) patients, 75 (63.6%) of whom had poor profiles. MRD was detected in 34 (31.2%) patients out of 109 evaluable patients who underwent surgery. Using multivariable analysis, pretreatment poor profiles and post-operative MRD were significantly associated with shorter recurrence-free survival (RFS) [hazard ratio (HR) 3.28, 95% confidence interval (CI) 1.72-6.25; HR 4.07, 95% CI 2.40-6.90, respectively] and time to surgical failure (TSF) (HR 2.76, 95% CI 1.35-5.64; HR 3.05, 95% CI 1.70-5.45, respectively). Patients with both poor pretreatment profiles and post-operative MRD demonstrated the worst prognosis in RFS (HR 13.28, 95% CI 5.86-30.10), TSF (HR 8.98, 95% CI 3.77-21.40), and overall survival (HR 9.21, 95% CI 2.06-41.18).
Conclusions
Combining pretreatment CGP and post-operative MRD in ctDNA showed potential for improved prognostic stratification after CRM resection.
