Unlocking the diagnostic potential of extracellular vesicles in cancer

Extracellular vesicles (EVs) are nanoscale lipid bilayer particles that are secreted by virtually all cells into biofluids; their cargo of nucleic acids, proteins, lipids, and glycans is tumor type and status informative and can be measured via minimally invasive liquid biopsy. Herein, we evaluate critically the EV-based assay diagnostic accuracy in both solid and hematologic malignancies, particularly with regard to exemplar biomarker panels and single-part analytics for pancreatic, prostate, breast, lung, and colorectal cancers as well as hematologic disorders. We emphasize newer immune- and affinity-directed isolation/phenotyping technologies that are more selective and scalable than conventional ultracentrifugation—e.g., microarray capture (EV Array), EV enrichment from cancer cells, magnetic nanopore capture, and filtration/thermophoretic routes—along with single-EV readouts for increased informational content. We also put EV diagnostics in a complementary role to established liquid biopsy modalities (e.g., ctDNA/cfDNA) to maximize detection and disease monitoring, rather than as alternatives. Finally, we outline theranostic applications, including engineered EVs as delivery vehicles and stromal EVs as therapy resistance biomarkers and mediators, to bridge diagnostics with interventional strategies. This roadmap centers clinically meaningful use cases and methodological stringency to drive translation of EV assays into oncology practice.