Sarcomatoid Renal Cell Carcinoma with an Unusually Rapid Fatal Course

Abstract

Sarcomatoid renal cell carcinoma is an uncommon neoplasm consisting of typical renal cell carcinoma associated intimately with a sarcomatoid component. The prognosis is known to be very poor. We present an autopsy case of sarcomatoid renal cell carcinoma that went through a highly fulminant lethal course. The patient was a 62-year-old male with left flank pain and weight loss. Computed tomograph and aortogram revealed a left renal mass growing out into the retroperitoneum. Multiple metastatic nodules were detected in the lungs and bone. Histologically the tumor showed features of anaplastic carcinoma, malignant fibrous histiocytoma and fibrosarcoma. Immunohistochemical studies of tumor revealed positive staining for cytokeratin (CAM 5.2). We interpreted this tumor as a sarcomatoid renal cell carcinoma extending into the retroperitoneum. He died of respiratory failure secondary to massive lung and mediastinal involvement of the tumor masses.