Rosai-Dorfman disease presenting as a parotid mass.

Sinus histiocytosis with massive lymphadenopathy (SHML) is a rare, benign disease of unknown aetiology. This disease typically presents with massive, painless cervical lymphadenopathy but may occur in a wide variety of extranodal sites. Our report describes a 71-year-old man who presented with a discrete, unilateral parotid mass which was clinically suggestive of a primary salivary gland tumour. Initial cytological examination of a fine needle aspirate specimen taken from the mass demonstrated a discohesive cell population with nuclear atypia, raising the possibility of malignancy. However, excision of the mass and histological examination enabled a definitive diagnosis to be made.