An extracellular vesicle-based assay for early detection of pancreatic ductal adenocarcinoma.

e16463 Background: Pancreatic ductal adenocarcinoma (PDAC) is among the deadliest cancers, primarily due to its late-stage diagnosis. This study focuses on developing a non-invasive diagnostic assay leveraging extracellular vesicles (EVs) to detect PDAC in its early stages. Methods: A PDAC EV Assay was designed to quantify PDAC-specific EV subpopulations in 300-μL plasma samples using a two-step workflow. First, EVs were enriched through click chemistry-based capture with EV Click Beads and antibodies grafted with trans-cyclooctene, targeting three PDAC-specific EV surface markers: MUC1, EGFR, and TROP2. Second, the enriched EVs were quantified using RT-qPCR. The three surface proteins were identified through a bioinformatics pipeline and validated with PDAC cell lines and tissue microarrays. Results: The PDAC EV Score, calculated from signals of MUC1 + , EGFR + , and TROP2 + PDAC EV subpopulations, demonstrated exceptional diagnostic performance in distinguishing PDAC patients from noncancer controls. The assay achieved areas under the receiver operating characteristic curve of 0.94 in the training cohort (n = 124) and 0.93 in the validation cohort (n = 136). Conclusions: This innovative EV-based diagnostic assay harnesses PDAC-specific EV subpopulations as biomarkers for early detection, translating tumor surface protein discoveries into a practical liquid biopsy platform for improved non-invasive diagnostics.