Detection, significance and potential utility of circulating tumor cells in clinical practice in breast cancer (Review).

Although advances in diagnostic techniques, new therapeutic strategies and personalization of breast cancer (BC) care have improved the survival for a number of patients, BC remains a major cause of morbidity and mortality for women. The study of circulating tumor cells (CTCs) has significant potential in translational oncology since these cells represent promising biomarkers throughout the entire course of BC in patients. CTCs also have notable prognostic value in early BC as well as metastatic BC. Based on current knowledge, it seems that the dynamics of CTCs that change during therapy reflect therapy response, and CTCs could serve as a tool for risk stratification and real-time monitoring of treatment in patients with BC. The question of how to use this information in everyday clinical practice and how this information can guide or change therapy to affect the clinical outcome of patients with BC remains unanswered. The present review aims to discuss current completed and ongoing trials that have been designed to demonstrate the clinical significance of CTCs, offer insights into treatment efficacy and assess CTC utility, facilitating their implementation in the routine management of patients with BC.