Sinus histiocytosis with massive lymphadenopathy (Rosai-Dorfman disease): case report with nodal and diffuse muco-cutaneous involvement.

Sinus histiocytosis with massive lymphadenopathy (SHML) (Rosai-Dorfman disease) is a rare self-limited histiocytic disorder of unknown origin, usually present with cervical lymphadenopathy, fever, elevated ESR and haematologic abnormalities. Extranodal lesions may occur as initial manifestations of the disease. In most cases skin lesions are associated with nodal or extranodal localization. A 54-year-old male is reported who, for a period of ten months, presented numerous slowly enlarging, rounded papular lesions on the face, neck, trunk as well as severe cervical lymphadenopathy without general and haematological disturbances. Thereafter a fungating mass developed in the nasal cavity. Histological, histochemical and immunohistochemical tests of skin, mucosal and lymph-node lesions were consistent with a diagnosis of SHML. The immunohistochemical characterization of the cytophagocytic S-100+ macrophages revealed that they were highly positive for the adhesion molecules Vitronectin receptor av/b3, which is used by tissue macrophages for removal of effete cells through phagocytosis.