Utility of Urinary Extracellular Vesicles for Colorectal Cancer: Comparison of DNA Quality and MRD Detection.
Summary
This study investigated the utility of urinary extracellular vesicles (EVs) as a liquid biopsy source for colorectal cancer (CRC). Urinary EVs demonstrated superior purity and DNA quality compared to plasma and urinary cell-free samples. Detecting RAS/BRAF mutations in urinary EV-DNA after curative surgery allowed for minimal residual disease (MRD) identification. MRD positivity was strongly associated with an increased risk of recurrence and inferior overall survival. These findings suggest that urinary EV-DNA is a promising tool for postoperative monitoring and risk stratification in CRC patients.
Analysis
Clinique: This cohort study evaluates urinary EV-DNA as a prognostic biomarker for minimal residual disease (MRD) detection after curative CRC surgery. The detection of RAS/BRAF mutations in urinary EV-DNA one month post-surgery strongly correlates with an increased recurrence risk (HR 5.25) and worse overall survival, making it a valuable risk stratification tool. This could justify clinical trials evaluating adjuvant therapies in MRD-positive patients and potentially change clinical practice for postoperative monitoring within 3-5 years. Biomol: The study discovered that urinary EVs provide a high-quality DNA source, with superior concentration and integrity compared to plasma and urinary cell-free samples, evidenced by a higher Long/Short fragment ratio. The technology used involves DNA extraction from EVs for specific mutation detection (RAS/BRAF). Mutation detection sensitivity in urinary EV-DNA (34.0%) is comparable to plasma ctDNA (39.2%), validating its potential for non-invasive molecular profiling and MRD detection.