In 2014, tumor‐derived exosomes were introduced as novel biomarkers containing tumor‐specific DNA from PDAC.48 microRNA have demonstrated very high accuracy for discriminating PDAC patients from pancreatitis patients and healthy controls.2, 49 Recently, it was reported that microRNA is useful for detecting early‐stage cancer.2, 49, 50 Melo et al50 identified the cell surface proteoglycan glypican‐1 (GPC1) on tumor‐derived exosomes. Here, GPC1 is linked to neoplasm.