Adenomatoid hyperplasia of pancreas presenting as tumor.

Adenomatoid hyperplasia belongs to the group of hyperplastic duct lesions of the pancreas. We report a 60-year-old man with adenomatoid hyperplasia of the pancreas, presenting as a mass lesion. The patient underwent pancreatico-duodenectomy uneventfully. The unusual location of the mass in the head of pancreas, the imaging and macroscopic appearance, dense fibrous stroma on histology and prominent expression of p21ras protein point towards a distinct subtype.