MUC1 and pancreatic intraductal papillary-mucinous neoplasm: The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of KL-6 concentration alone, and with PJC, were all 100% when the cut-off level of KL-6 concentration was from 32.7 to 39.4 U/mL for differentiating IPMC from IPMN.