Liquid biopsy in bladder cancer: towards precision oncology

Bladder cancer (BC), as the most common form of urothelial carcinoma, represents a substantial global health burden owing to its high rates of late diagnosis and disease recurrence. Current standard diagnostics, such as cystoscopy and tissue biopsy, are invasive, costly, and limited in capturing tumor heterogeneity or enabling longitudinal monitoring. These constraints underscore the urgent need for minimally invasive, reliable biomarkers. Over the past decade, liquid biopsy has emerged as a transformative, non-invasive alternative, enabling the dynamic profiling of circulating tumor-derived components like circulating tumor DNA (ctDNA), circulating tumor cells (CTC), and extracellular vesicles (EVs). This review comprehensively synthesizes the role of these liquid biopsy analytes in advancing the early detection, prognostic stratification, treatment response monitoring, and immunophenotyping of Urothelial Carcinoma(UC). We critically evaluate the underlying technological advances, consolidate key clinical evidence, discuss persisting challenges, and outline the translational path toward integrating liquid biopsy into precision oncology paradigms for BC management.