Rosai-Dorfman disease with sinonasal mucosal involvement.

Rosai-Dorfman disease (RDD) or sinus histiocytosis with massive lymphadenopathy (SHML) is a rare benign disorder that typically manifests as massive lymphadenopathy and systemic symptoms. The authors report a 27-year-old man who presented with nasal mass and generalised cervical lymphadenopathy. Cytological and histopathological examination of lymph nodes demonstrated lymphophagocytosis (emperipolesis) consistent with a diagnosis of RDD. There was remarkable regression in the size of nasal polyps and lymph nodes after systemic corticosteroids. The clinical and histological aspects of the disease are discussed as a rare cause of generalised lymphadenopathy.