[Rosai-Dorfman disease limited to the skin. Four case reports].

Sinus histiocytosis with massive lymphadenopathy (SHML), or Rosai-Dorfman Disease, presents with bilateral painless cervical adenomegaly, fever, and several hematologic abnormalities. Skin is the extranodal site most frequently affected. We described four additional cases of SHML limited to the skin, emphasizing possible confusion with other dermatoses. Clinical, morphologic, and immunohistochemical aspects of four patients with cutaneous SHLM, three diagnosed in the ABC Medical Center in Mexico City and the other at the Hermanos Ameijeiras Hospital of Havana, Cuba, are reviewed. Three males and one female, 48, 35, 42, and 55 years of age, presented with chronic asymptomatic dermal nodules, papules, or plaques on trunk, extremities, and face. Skin biopsies showed dense infiltrates of foamy histiocytes, lymphocytes, and plasma cells; histiocytes presented with prominent emperipolesis and intense S100 and CD68 immunostain. The four cases reported here had histiocytic benign proliferative disorder corresponding with cutaneous SHML: Emperipolesis suggested the diagnosis. Immunohistochemistry demonstrated positivity for S100 protein in macrophages. Cutaneous lesions of SHML are easily recognized when they are found in the classical clinical picture, but as purely skin disease could be confused with other dermatoses.