Vimentin-Positive Circulating Tumor Cells as Diagnostic and Prognostic Biomarkers in Patients with Biliary Tract Cancer.

Biliary tract cancer (BTC) has poor prognosis; thus, early diagnosis is important to decrease mortality. Although vimentin-positive circulating tumor cells (V-CTCs) are a good candidate for diagnostic and prognostic biomarkers, studies on the topic are limited. We aimed to evaluate the diagnostic efficacy of V-CTCs between BTC and benign biliary disease (BBD) and determine the prognostic value of V-CTCs in BTC patients. We recruited 69 participants who had BTCs and BBDs from a single tertiary referral center. We analyzed CTCs and V-CTCs in peripheral blood using the CD-PRIMETM system. Seven patients were excluded due to a technical failure of CTC detection. CTCs were detected in all 62 patients. CTC count > 40/mL blood (55.8% vs. 20%, p = 0.039), V-CTC count > 15/mL blood (57.7% vs. 10%, p = 0.005), and V-CTC/CTC ratio > 40% (48.1% vs. 10%, p = 0.025) were significantly different between BTCs and BBDs. Two or more of these three parameters (61.5% vs. 10%, p = 0.002) increased the accuracy. A combination of CTC markers with CA19-9 and biopsy increased the accuracy (90.4% vs. 10%, p = 0.000). V-CTC > 50/mL blood was a significant factor affecting survival (140 (66.6-213.3) vs. 253 (163.9-342.1) days, p = 0.008). V-CTC could be a potential biomarker for early diagnosis and predicting prognosis in patients with BTC.