rosai-dorfman disease with pure and multifocal cutaneous lesions: a case report

A 52‐year‐old woman developed progressive infiltrated purple and hyperpigmented cutaneous lesions in the face, thighs, armpits, chest, and abdomen evolving forone year. histopathological examination showed large histiocytes exhibiting intact inflammatory cells in their cytoplasm (emperipolesis). immunohistochemical analyses showed that the histiocyte population was positive for s100 and cd68, but negative for cd1a. based on the clinical, histopathological, and immunohistochemical findings, we made the diagnosis of rosai dorfman disease (rdd). our patient didn’t manifest any other extra-cutaneous involvement and all the biological and radiological investigations were normal. this form of pure cutaneous rdd (p-crdd) with multifocal lesions has been rarely reported. rdd is very rare and hardly recognized in the absence of lymphadenopathy. the diagnosis of this entity involves a combination of histology and immunohistochemistry. to date, there is no standard treatment.