Integrating extracellular vesicle and circulating cell-free DNA analysis using a single plasma aliquot improves the detection of HER2 positivity in breast cancer patients.

Multi-analyte liquid biopsies represent an emerging opportunity for non-invasive cancer assessment. We developed ONCE (One Aliquot for Circulating Elements), an approach for the isolation of extracellular vesicles (EV) and cell-free DNA (cfDNA) from a single aliquot of blood. We assessed ONCE performance to classify HER2-positive early-stage breast cancer (BrCa) patients by combining EV-associated RNA (EV-RNA) and cfDNA signals on  = 64 healthy donors (HD) and non-metastatic BrCa patients.