Case of a concurrent renal mass and extragonadal retroperitoneal teratoma

The presentation of a synchronous renal cell carcinoma (RCC) and germ cell tumor (GCT) is rare. We report the case of a 57 year-old male who presented with a right renal mass and retroperitoneal lymphadenopathy. He underwent a successful right partial nephrectomy and retroperitoneal lymph node dissection, and the subsequent pathology revealed a stage I clear cell RCC and a retroperitoneal teratoma with a component of benign prostatic tissue. We briefly discuss the rarity of this occurrence, the pathological features that helped support this diagnosis, and the likely etiologies of these synchronous lesions.