OBJECTIVESRobust biomarkers for pancreatic cancer (PaC) early detection/prognosis are critical for improved patient survival. Our goal was to explore the biomarker potential of 5-hydroxymethylcytosines (5hmC), an epigenetic marker with a distinct role in cancer pathobiology, yet under-investigated due largely to technical constraints.\n\nMETHODSWe used the TAB-Array assay, a state-of-the-art technology to directly profile 5hmC at single base resolution with the Illumina EPIC array (>850,000 CpG sites) in 17 pairs of tumor/adjacent tissue samples from US patients.\n\nRESULTSWe demonstrated distinctive distributions of 5hmC in tissues, and substantial differences between tumor and adjacent tissues, suggesting their diagnostic/prognostic value of for PaC.\n\nCONCLUSIONThis study established the potential of 5hmC as a novel epigenetic biomarker for PaC.