Diagnostic and Prognostic Utility of Cell-Surface Vimentin Positive Circulating Tumor Cells in Breast Cancer Using an...

Background/Objectives: Breast cancer (BC) is the most commonly diagnosed cancer in women, and metastasis is the leading cause of BC-related death. Circulating tumor cells (CTCs) are a prerequisite for metastasis. This study examined the diagnostic and prognostic value of CTCs for assessing metastatic risk and recurrence in BC. Methods: The Chiline CATCH^® Circulating Target Cell Enrichment System, an automated negative selection platform, was used to enrich and enumerate CTCs from the peripheral blood of patients with BC. Epithelial cell adhesion molecule (EpCAM) and cell-surface Vimentin (CSV) were used as markers for CTC identification. Results: CSV⁺ CTC counts, but not EpCAM⁺ CTC counts, were increased in patients with BC at higher metastatic risk. A cut-off of >4.5 CSV⁺-CTCs/2 mL blood yielded a sensitivity of 0.56 and specificity of 0.92 for identifying patients at high metastatic risk. CSV⁺-CTCs outperformed conventional serum tumor markers, including cancer antigen 15-3 (CA 15-3), cancer antigen 125 (CA 125), and carcinoembryonic antigen (CEA), in identifying patients with high metastatic risk, and their combined use further improved risk stratification. An elevated CSV⁺-CTC count (≥5 cells/2 mL blood) was significantly associated with worse progression-free survival in patients with BC. Conclusions: These findings suggest that CSV⁺-CTCs may serve as a biomarker for metastatic risk stratification and recurrence monitoring in BC when measured using an automated negative selection platform.