Rosai-Dorfman disease presenting with isolated bilateral orbital masses: report of two cases.

Rosai-Dorfman disease (sinus histiocytosis with massive lymphadenopathy) is a rare benign idiopathic proliferative disease of phagocytic histiocytes. Approximately 80% of patients present with painless massive cervical lymphadenopathy. Isolated extranodal involvement is relatively uncommon. Two cases of Rosai-Dorfman disease are reported: one with isolated bilateral orbital involvement and one with marked cervical lymphadenopathy and multiple dural-based and intraventricular masses.