(1) Background: Local therapies offer a potentially curative approach for patients with oligometastatic colorectal cancer (CRC). An evidence-based consensus recommendation for systemic therapy following definitive locoregional therapy is lacking. Tumor-informed circulating tumor DNA (ctDNA) might provide information to help guide management in this setting. (2) Methods: A multi-institutional retrospective study was conducted, including patients with CRC that underwent curative-intent locoregional therapy to an isolated site of metastatic disease, followed by tumor-informed ctDNA assessment. The Kaplan–Meier method and log-rank tests were used to compare disease-free survival based on ctDNA results. ctDNA test performance was compared to carcinoembryonic antigen (CEA) test results using McNemar’s test. (3) Results: Our study cohort consisted of 87 patients treated with locoregional interventions who underwent ctDNA testing. The initial ctDNA test post-intervention was positive in 28 patients and negative in 59 patients. The median follow-up time was 14.0 months. Detectable ctDNA post-intervention was significantly associated with early disease recurrence, with a median disease-free survival (DFS) of 6.63 months compared to 21.30 months in ctDNA-negative patients (p< 0.001). ctDNA detected a numerically higher proportion of recurrences than CEA (p< 0.097). Post-intervention systemic therapy was not associated with improved DFS (p= 0.745). (4) Conclusions: ctDNA results are prognostically important in oligometastatic CRC, and further prospective studies are urgently needed to define its role in guiding clinical decisions.
（1）背景：对于寡转移性结直肠癌患者，局部治疗提供了一种潜在根治性手段。目前缺乏关于根治性局部治疗后系统性治疗的循证共识建议。肿瘤知情循环肿瘤DNA检测可能为此类患者的治疗管理提供指导信息。（2）方法：本研究为多机构回顾性分析，纳入接受根治性局部治疗的孤立性转移灶CRC患者，并在治疗后进行肿瘤知情ctDNA检测。采用Kaplan-Meier法和时序检验比较不同ctDNA状态患者的无病生存期。通过McNemar检验比较ctDNA与癌胚抗原检测的效能差异。（3）结果：研究队列包含87例接受局部干预治疗并行ctDNA检测的患者。干预后首次ctDNA检测阳性28例，阴性59例。中位随访时间14.0个月。干预后ctDNA可检测状态与早期疾病复发显著相关：ctDNA阳性患者中位无病生存期6.63个月，显著低于阴性组的21.30个月（p<0.001）。ctDNA检测到的复发比例在数值上高于CEA检测（p<0.097）。干预后系统性治疗与无病生存期改善无显著关联（p=0.745）。（4）结论：ctDNA检测结果对寡转移性CRC具有重要预后价值，亟需前瞻性研究明确其在临床决策指导中的作用。
肿瘤(癌症)患者之家