EPCAM and neoplasm: Exosomes could be released by healthy and abnormal cells.15, 16 Serval studies have been reported that EpCAM contributes to ESCC cell proliferation and tumorigenesis and may be a useful therapeutic target for ESCC.17, 18 EpCAM magnetic beads were used in our study for tumor‐associated exosome purification to improve its accuracy and specificity for epithelial cancerous origin and avoid secondary interference from nonepithelial origin in a certain extent.