Cutaneous Rosai-Dorfman disease (RDD) is a rare entity of unknown origin and is not well documented, especially in Asian populations.

The purpose of this study was to evaluate the clinical manifestation, diagnostic histopathology, clinical course, and response to treatment of cutaneous RDD in Taiwan.

This study included 21 patients with cutaneous RDD who presented at our institution from 1995 to 2003. Pathologic examinations with both hematoxylin-eosin and immunohistochemical stains were reviewed, as were associated clinical features and therapeutic methods.

None of the 21 patients with cutaneous RDD had nodal lesions. The clinical manifestation was variable, but most commonly involved a central noduloplaque with satellite papules. One patient manifested as an ulcerated nodule, something not reported previously. Multifocal involvement only occurred in 4 patients. Concurrent involvement of uvea or vocal cord occurred in two patients. The most prominent histologic feature was a florid and mixed inflammatory infiltration. The phagocytosis of inflammatory cells into the cytoplasm of histiocytes, a process called “emperipolesis,” is a characteristic finding of nodular RDD but usually only focally presented in cutaneous ones. Positivity for S-100 protein helped to confirm the diagnosis. The most effective treatment was surgical excision of solitary lesions. High-dose thalidomide (300 mg/d), but not low-dose, was effective to control the extensive cutaneous diseases in two patients. A total of 3 patients experienced spontaneous remission 1 to 2 years after diagnosis.

Cutaneous RDD appeared more frequently in Asian populations than in reports from Western countries. The incidence of multifocal involvement in this series is much lower than in other literature. Although treatment of disseminated cutaneous RDD is difficult, high-dose thalidomide (300 mg/d), which was effective in two patients in this series, may be helpful.