Rosai-Dorfman disease involving the neurohypophysis

Rosai-Dorfman disease is a rare, histiocytic proliferative disorder of unknown etiology commonly affecting lymph nodes. Extranodal lesions with or without nodal involvement also occur. We report the case of a 63 year-old woman with disseminated Rosai-Dorfman disease involving the neurohypophysis and associated with adenohypophysial PRL cell hyperplasia.