Circulating tumor cells and cholangiocarcinoma

Circulating tumor cells (CTCs) are shed from a primary tumor and can lead to metastasis. Modern techniques to detect these cells in the peripheral blood of patients have been developed over the past two decades, with early reports showing increased numbers of CTCs in cancer patients compared to controls and higher CTC numbers associated with more progressive disease [e.g., (1)]. Since then, studies have reported that higher peripheral CTCs associate with reduced survival in cancers of the breast, colon, bladder, prostate, ovary, and lung, and in hepatocellular carcinoma (HCC) (2-7). CTC enumeration has therefore been suggested as a possible cancer-screening tool, or as an instrument of prognostication.