Biosensors based on liquid biopsy for clinical cancer diagnosis

Cancer remains a leading cause of global mortality, with incidence and death rates continuing to rise annually, posing an escalating threat to human health. Early detection is paramount for effective intervention, significantly improving patient survival rates by enabling timely treatment when therapeutic options are most viable. However, conventional diagnostic methodologies, often reliant on sophisticated imaging techniques or centralized laboratory analyses of tissue biopsies, face significant limitations. Consequently, the development of accessible and accurate diagnostic tools is of profound significance for improving cancer management outcomes. Liquid biopsy, a minimally invasive approach analyzing tumor-derived biomarkers in readily accessible bodily fluids (e.g., blood, serum, plasma, urine, saliva), represents a particularly promising application for cancer detection. This comprehensive review critically examines the current landscape of sensors specifically designed for the point-of-care detection of tumor biomarkers in bodily fluids, with a deliberate focus on technologies demonstrating clear clinical relevance. We prioritize the discussion of devices that have undergone rigorous validation using authentic clinical samples (patient-derived fluids) and, where available, systems that have progressed to implementation within clinical practice.