Renal Angiomyolipoma With Sarcoid Granulomas: Report of a Unique Case.

Angiomyolipoma is a mesenchymal neoplasm characterized by the coexpression of melanocytic and smooth muscle markers. Sarcoidosis is a multisystem disorder of unknown etiology, which presents with characteristic nonnecrotizing granulomas and rarely involves the kidney. The coexistence of renal sarcoidosis with renal neoplasms is exceedingly rare and was reported only with renal cell carcinoma. Renal sarcoidosis associated with a nonepithelial renal neoplasm, such as an angiomyolipoma has never been reported. We present the first reported case of sarcoid granulomas in a renal angiomyolipoma, including morphologic and immunohistochemical features.