Sarcomatoid Renal Cell Carcinoma

Abstract

Histologically, the sarcomatoid variant of renal cell carcinoma (SRCC) is a pleomorphic spindle or giant cell malignancy resembling a sarcoma. Clinically, SRCC is associated with a worse prognosis than common renal cell carcinoma (CRCC) of clear or granular cell types. The authors reviewed the clinical and pathologic findings in five cases of SRCC and performed avidin-biotin peroxidase staining with Leu-M1 and biotinylated lotus tetragonolobus lectin, which react with proximal tubules, biotinylated soybean and dolichos biflorus agglutinins, which react with distal tubules, cytokeratin AE 1, epithelial membrane antigen, and vimentin. Five of five SRCCs reacted with at least one marker of proximal tubular differentiation. No case reacted with distal tubular differentiation markers. Three of five cases were cytokeratin positive, one of five was epithelial membrane antigen positive, and zero of five were vimentin positive. Since most cases of CRCC react with proximal tubular markers, these findings suggest that SRCC is a histologic subtype of CRCC rather than a distinct histogenetic entity. Int J Surg Pathol 1 (2):107-110, 1993