SMAD4 and neoplasm: The outlier sample was a very differentiated tumor from a 60-year-old woman, which, surprisingly, was wild-type for KRAS, SMAD4, CDKN2A, and p53 alleles, and displayed expression profiles and methylation patterns that were not characteristic of previously described pancreatic cancer tumors, suggesting that it may have been either clinically misclassified or represented a very rare type of pancreatic cancer not previously described.