MUC4 and pachyonychia congenita: Additionally, the assessment of the diagnostic accuracy of mutant KRAS oncogene detection from pancreatic juice in PC revealed a wide range of variation in sensitivity (38%–89%) and specificity (13%–100%); the DNA methylation status of MUC1, MUC2, and MUC4 for the differential diagnosis of human pancreatic neoplasms had a sensitivity and specificity of 87% and 80% for PC; and methylated ppENK and p16 were found in the pancreatic juice of patients with PC in 90.9% and 18.2% of cases, respectively [186,187,188].