[Rosai-Dorfman disease as a rare cause of a pancreatic mass].

The CT and MRI scans of a 70-year-old male patient revealed a mass in the pancreatic head and a 2.8-cm peripancreatic lymph node. Under steroid therapy the mass did not show regression. Finally, a pancreatoduodenectomy was performed. Histologically, Rosai-Dorfman disease (RDD) was diagnosed. RDD is a rare histiocytic disorder with usually nodal but sometimes also extranodal involvement. Herein we report a rare case of extranodal RDD with intrapancreatic localization.