Circulating tumor cells in metastatic breast cancer: ready for clinical practice?

Circulating tumor cells (CTCs) have emerged as a promising new biomarker in breast cancer and various settings in which liquid biopsy may improve diagnostics are currently under discussion. In patients with metastatic disease, high CTC counts have been shown to predict poor prognosis with level I evidence. Persistence of elevated CTC numbers after begin of systemic treatment is associated with higher risk of progression. This review discusses current evidence on the clinical use of CTC diagnostics in metastatic breast cancer.

circulating tumor cells; CTCs; liquid biopsy; breast cancer; metastatic breast cancer; therapy interventions

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