Unveiling the Timeline of Liquid Biopsy Analytes Release: Review of the Implications for Early Cancer Detection

Background:Liquid biopsy has revolutionized cancer diagnostics by providing a minimally invasive means of capturing tumor-derived biomarkers from body fluids. Unlike conventional tissue biopsy, it enables real-time monitoring of tumor heterogeneity and evolution. Circulating tumor DNA (ctDNA), circulating tumor cells (CTCs), exosomes, and microRNAs (miRNAs) represent the most clinically relevant analytes, each with distinct mechanisms and timing of release into circulation. Methods:This review synthesizes recent global, Sub-Saharan African, and Nigerian literature published within the last decade. Emphasis is placed on comparative mechanisms of analyte release, timing in the cancer continuum, and translational applications in detection, monitoring, and therapeutic stratification. Key advances and challenges in clinical utility, especially in resource-limited settings, are highlighted. Results:ctDNA offers high sensitivity for early detection and mutational profiling, while CTCs provide insights into metastatic potential and treatment resistance. Exosomes and miRNAs act as stable carriers of genetic and proteomic information, expanding diagnostic and prognostic possibilities. Integration of multi-analyte approaches enhances sensitivity and specificity across cancer types. However, significant barriers including infrastructural limitations, cost, and lack of standardized protocols—hamper adoption in low- and middle-income countries. Conclusion:Liquid biopsy represents a paradigm shift in oncology, enabling early diagnosis, personalized treatment, and dynamic disease monitoring. Future directions include multi-analyte platforms combined with artificial intelligence, standardized assays, and equitable global access. Region-specific validation in Sub-Saharan Africa and Nigeria remains essential to ensure its translation into clinical practice and maximize impact.