Maria Papadaki, PhD, University of Crete, Heraklion, Greece, talks on the findings of a study investigating the effects of TLR4 and pSTAT3 expression on circulating tumor cells (CTCs) in patients with metastatic breast cancer. Peripheral blood samples were analyzed from 100 patients with metastatic breast cancer prior to first-line therapy. The study reported that TLR4+/pSTAT3+ CTCs were most common in patients with triple-negative breast cancer compared to HR+/HER2- and HER2+ subtypes. The detection of cytokeratin (CK)+ CTCs was associated with shorter overall survival, and detection of TLR4+ CTCs was associated with a shorter progression-free survival. Overall, the study concluded that analysis of TLR4 and pSTAT3 expression on CTCs could be useful in determining prognosis in patients with metastatic breast cancer. This interview took place at the virtual European Society for Medical Oncology (ESMO) Breast Cancer Congress 2021.