Background There is accumulating evidence supporting the clinical use of circulating tumor DNA (ctDNA) in solid tumors, especially in different types of gastrointestinal cancer. As such, appraisal of the current and potential clinical utility of ctDNA is needed to guide clinicians in decision-making to facilitate its general applicability. Content In this review, we firstly discuss considerations surrounding specimen collection, processing, storage, and analysis, which affect reporting and interpretation of results. Secondly, we evaluate a selection of studies on colorectal, esophago-gastric, and pancreatic cancer to determine the level of evidence for the use of ctDNA in disease screening, detection of molecular residual disease (MRD) and disease recurrence during surveillance, assessment of therapy response, and guiding targeted therapy. Lastly, we highlight current limitations in the clinical utility of ctDNA and future directions. Summary Current evidence of ctDNA in gastrointestinal cancer is promising but varies depending on its specific clinical role and cancer type. Larger prospective trials are needed to validate different aspects of ctDNA clinical utility, and standardization of collection protocols, analytical assays, and reporting guidelines should be considered to facilitate its wider applicability.

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解释循环肿瘤 DNA 在胃肠道癌症治疗中的实用方法

背景 越来越多的证据支持循环肿瘤 DNA (ctDNA) 在实体瘤中的临床应用，特别是在不同类型的胃肠道癌症中。因此，需要评估 ctDNA 当前和潜在的临床效用，以指导临床医生决策，以促进其普遍适用性。内容 在本次综述中，我们首先讨论有关样本采集、处理、储存和分析的考虑因素，这些因素会影响结果的报告和解释。其次，我们评估了一系列关于结直肠癌、食管胃癌和胰腺癌的研究，以确定在疾病筛查、分子残留病 (MRD) 检测和监测期间疾病复发、治疗评估中使用 ctDNA 的证据水平反应，指导靶向治疗。最后，我们强调了 ctDNA 临床应用目前的局限性和未来的方向。总结 目前 ctDNA 在胃肠道癌症中的证据是有希望的，但根据其具体的临床作用和癌症类型而有所不同。需要更大规模的前瞻性试验来验证 ctDNA 临床效用的不同方面，并且应考虑收集方案、分析测定和报告指南的标准化，以促进其更广泛的适用性。