title: Renal sinus histiocytosis.
abstract: A 26-year-old woman had an infiltrative renal lesion accompanied by massive regional lymphadenopathy. Biopsy of the renal mass and a coexistent orbital mass revealed identical histologic evidence of sinus histiocytosis. This unusual benign entity is uncommon in the kidney, but radiographically, it may closely simulate an infiltrative renal neoplasm, especially a lymphoma or leukemia or even renal cell carcinoma.
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007674:Kidney Diseases / Q000175:diagnosis*; D008206:Lymphatic Diseases / Q000175:diagnosis*