胃肠道（GI）癌症包含许多癌症类型，如食管癌、肝癌、胃癌、胰腺癌和结直肠癌。作为GI癌症个体化医学的基石，基于非侵入性生物标志物的液体活检为早期诊断和动态治疗管理提供了有希望的机会。最近，越来越多的研究表明，游离RNA（cfRNA）作为一种新型的身体液体生物标志物具有潜力，如血液、唾液和尿液等。同时，基于高通量RNA检测技术的转录组不断发现新的cfRNA生物标志物。在本综述中，我们介绍cfRNA的起源和应用，描述其在液体活检中的检测和合格方法，并总结不同GI癌症类型中的广泛cfRNA生物标志物列表。此外，我们还讨论了cfRNA未来的研究，以克服其在临床应用中的局限性。该文章归类于：疾病和发展中的RNA > 疾病中的RNA。©2023 Wiley Periodicals LLC.

Gastrointestinal (GI) cancer includes many cancer types, such as esophageal, liver, gastric, pancreatic, and colorectal cancer. As the cornerstone of personalized medicine for GI cancer, liquid biopsy based on noninvasive biomarkers provides promising opportunities for early diagnosis and dynamic treatment management. Recently, a growing number of studies have demonstrated the potential of cell-free RNA (cfRNA) as a new type of noninvasive biomarker in body fluids, such as blood, saliva, and urine. Meanwhile, transcriptomes based on high-throughput RNA detection technologies keep discovering new cfRNA biomarkers. In this review, we introduce the origins and applications of cfRNA, describe its detection and qualification methods in liquid biopsy, and summarize a comprehensive list of cfRNA biomarkers in different GI cancer types. Moreover, we also discuss perspective studies of cfRNA to overcome its current limitations in clinical applications. This article is categorized under: RNA in Disease and Development > RNA in Disease.© 2023 Wiley Periodicals LLC.