Sarcomatoid renal carcinoma with angiosarcomatoid component. Light macroscopic and immunohistochemical study
We describe a case of primary renal pelvic carcinoma which showed an unusual histologic pattern of anastomosing blood-filled channels lined by atypical cells. This angiosarcomatoid pattern merged with solid areas typical of renal carcinoma. Immunoperoxidase stains for cytokeratin and epithelial membrane antigen were positive in both the angiosarcomatoid and typical carcinomatous areas, while stains for factor VIII-related antigen and desmin were negative. Since primary renal angiosarcomas are rare neoplasms, the diagnosis of sarcomatoid renal carcinoma should be considered in primary renal neoplasms which show this angiosarcomatoid pattern.