Peripheral blood of cancer patients "physiologically" presents cells and cellular components deriving from primary or metastatic sites, including circulating tumor cells (CTCs), circulating free DNA (cfDNA) and exosomes containing proteins, lipids and nucleic acids. The term circulating tumor DNA (ctDNA) indicates the part of cfDNA which derives from primary tumors and/or metastatic sites, carrying tumor-specific genetic or epigenetic alterations. Analysis of ctDNA has enormous potential applications in all stages of cancer management, including earlier diagnosis of cancer, identification of driver alterations, monitoring of treatment response and detection of resistance mechanisms. Thus, ctDNA has the potential to profoundly change current clinical practice, by moving from tissue to peripheral blood as a source of information. Herein, we review current literature regarding the potential role for ctDNA in biliary tract cancer (BTC) patients, with a particular focus on state-of-the-art techniques and future perspectives of this highly aggressive disease.

中文翻译：

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胆道癌中的循环肿瘤 DNA：当前证据和未来展望。


癌症患者的外周血“生理上”呈现源自原发或转移部位的细胞和细胞成分，包括循环肿瘤细胞（CTC）、循环游离DNA（cfDNA）和含有蛋白质、脂质和核酸的外泌体。循环肿瘤 DNA (ctDNA) 一词表示源自原发性肿瘤和/或转移部位的 cfDNA 部分，携带肿瘤特异性遗传或表观遗传改变。 ctDNA 分析在癌症管理的各个阶段都具有巨大的潜在应用，包括癌症的早期诊断、驱动基因改变的识别、治疗反应的监测和耐药机制的检测。因此，ctDNA 作为信息来源从组织转移到外周血，有可能深刻改变当前的临床实践。在此，我们回顾了有关 ctDNA 在胆道癌 (BTC) 患者中潜在作用的最新文献，特别关注这种高度侵袭性疾病的最先进技术和未来前景。