Rosai-Dorfman disease of the paranasal sinuses and orbit.

Rosai-Dorfman disease, also known as sinus histiocytosis with massive lymphadenopathy, is a benign indolent disorder, characterized by enlarged lymph nodes filled with histiocytes. Extranodal involvement is uncommon. The disease rarely affects the nose and paranasal sinuses. We report a case that presented with a right nasal mass, extending into all the paranasal sinuses and right orbit without any accompanying lymphadenopathy. Because of the absence of lymphadenopathy it posed a diagnostic challenge until the pathology was confirmed on histopathological examination.