Abstract
Breast cancer (BC) remains a leading cause of morbidity and mortality among women worldwide, necessitating the development of innovative diagnostic and monitoring strategies. Liquid biopsy (LB), a minimally invasive approach that analyzes circulating tumor cells (CTCs), cell-free DNA (cfDNA), circulating tumor DNA (ctDNA), extracellular vesicles (EVs), and other tumor-derived biomarkers in body fluids, has emerged as a transformative tool in BC management. This review comprehensively explores the role of LB in early detection, disease monitoring, treatment stratification, and resistance surveillance in BC. We discuss the latest advancements in LB technologies, including next-generation sequencing (NGS), digital PCR, and single-cell analysis, highlighting their sensitivity and specificity. Additionally, we examine the clinical utility of LB in guiding personalized therapy, particularly in the context of hormone receptor-positive, HER2positive, and triple-negative BC subtypes. Despite its promise, several challenges, including standardization, validation, and integration into clinical practice, remain to be addressed. By summarizing current evidence and future directions, this review underscores the potential of LB to revolutionize BC diagnosis and treatment, paving the way for a more precise and dynamic approach to disease management.