Cutaneous Rosai-Dorfman disease.

Cutaneous Rosai-Dorfman disease (CRDD) is a rare form of Rosai-Dorfman disease (RDD)(also known as sinus histiocytosis with massive lymphadenopathy) that has a varied clinical presentation, an unknown etiology, and multiple treatment options that lack efficacy. We present a case of a 31-year-old woman who presented with grouped flesh-colored to light pink papules and plaques within a hyperpigmented patch on the thigh that were treated with topical, oral, and intralesional steroids with minimal improvement.