Advances in Liquid Biopsy: Circulating Biomarkers of Cancer Progression and Metastases

To date, tissue biopsy techniques for tumors are inferior to newer liquid biopsy (LB) technologies due to their convenience and informative nature. LB is a concept that has gained increasing attention due to its non-invasive nature and ability to analyze tumor status in real time. Samples for LB can include blood, urine, stool, saliva, pleural fluid, and cerebrospinal fluid. LB is one of the primary strategies for detecting tumor-associated biomarkers such as circulating tumor cells (CTCs), genetic markers (DNA, micro RNA (miRNA), messenger RNA (mRNA), tumor-educated platelets, and extracellular vesicles (EVs). These biomarkers enable real-time monitoring of tumor evolution and therapeutic response, which improves clinical decision-making at different stages of cancer treatment.