Radiation response of Rosai-Dorfman disease presenting with involvement ofthe orbits

The purpose of this study was to review an interesting case of recurrent or bital sinus histiocytosis. The patient initially failed surgery, chemothera py, and steroid therapy, only to have a durable response to low-dose radiat ion therapy of the orbits, lasting 6 and 11 years, respectively. Because th ere are few documented responses to radiotherapy, we present a case report in conjunction with the clinical, radiographic, and histopathologic informa tion as well as a literature review of similar cases.