Purely cutaneous Rosai-Dorfman disease

Summary Cutaneous lesions of Rosai-Dorfman disease (RDD) are usually associated with nodal or other extranodal localization. We describe a female patient with RDD clinically limited to the skin. The patient presented with asymptomatic red brown papules and nodules on the legs, arms, Back and nose. Histologically the lesions consisted of a proliferation of large histiocytes occasionally showing emperipolesis. Histiocytes were also observed within dilated lymphatic vessels. Immunohistochemical study showed that histiocytes expressed S-l protein and both macrophage and tonicity markers. All lesions resolved completely with Roentgen therapy. No recurrence has been observed over a 3-year follow-up period.