Liquid biopsy, a minimally invasive procedure that causes minimal pain and complication risks to patients, has been extensively studied for cancer diagnosis and treatment. Moreover, it facilitates comprehensive quantification and serial assessment of the whole-body tumor burden. Several biosources obtained through liquid biopsy have been studied as important biomarkers for establishing early diagnosis, monitoring minimal residual disease, and predicting the prognosis and response to treatment in patients with cancer. Although the clinical application of liquid biopsy in gastric cancer is not as robust as that in other cancers, biomarker studies using liquid biopsy are being actively conducted in patients with gastric cancer. Herein, we aimed to review the role of various biosources that can be obtained from patients with gastric cancer through liquid biopsies, such as blood, saliva, gastric juice, urine, stool, peritoneal lavage fluid, and ascites, by dividing them into cellular and acellular components. In addition, we reviewed previous studies on the diagnostic, prognostic, and predictive biomarkers for gastric cancer using liquid biopsy and discussed the limitations of liquid biopsy and the challenges to overcome these limitations in patients with gastric cancer.

中文翻译：

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液体活检：一种新兴的胃癌诊断、预后和预测工具。

液体活检是一种微创手术，对患者造成的疼痛和并发症风险最小，已被广泛研究用于癌症诊断和治疗。此外，它有利于全身肿瘤负荷的全面量化和连续评估。通过液体活检获得的几种生物来源已被研究作为重要的生物标志物，用于建立早期诊断、监测微小残留病以及预测癌症患者的预后和治疗反应。尽管液体活检在胃癌中的临床应用不如其他癌症那么强大，但使用液体活检的生物标志物研究正在胃癌患者中积极进行。在此，我们的目的是回顾通过液体活检从胃癌患者身上获得的各种生物来源的作用，例如血液、唾液、胃液、尿液、粪便、腹腔灌洗液和腹水，将其分为细胞和腹水。无细胞成分。此外，我们回顾了以前使用液体活检进行胃癌诊断、预后和预测生物标志物的研究，并讨论了液体活检的局限性以及在胃癌患者中克服这些局限性的挑战。