A case of orbital Rosai-Dorfman disease responding to radiotherapy

Rosai-Dorfman disease (RDD) is a rare histiocytic disorder most often characterized by painless cervical lymphadenopathy, but it may also present with orbital disease. The clinical course of RDD is variable; it can be either relapsing remitting or progressive, and the outcome relates to clinical location and treatment response. Orbital RDD can have an insidious onset and similar presentation to other ophthalmic conditions; this can result in a delayed diagnosis. Nearly all cases of orbital RDD cause visual disturbances and require treatment. Because orbital RDD is an uncommon presentation, a variety of interventions have been employed, Including surgery, immunotherapy, chemotherapy, and radiotherapy. We present a case of salvage radiotherapy for progressive orbital RDD refractory to surgery and chemotherapy in a pediatric patient.