Since Posen et al. reported the first case of an UC with OGCs of the pancreas associated with a mucus-secreting cystadenocarcinoma in 1981 [2], there have been 11 additional cases reported in the English language literature of UC with OGCs of the pancreas originating in MCN and indeterminate mucin-producing cystic neoplasm [2-12]. This evidence concerns the gene MUC5AC and cystadenocarcinoma.