Rare Metastatic Testicular Cancer in a Veteran.

Testicular yolk sac tumor (YST) is a nonseminomatous germ cell tumor that predominantly affects prepubescent boys. Pure endometrioid variant YST is rare, with only 1 report in the literature. We present the first reported case of en-dometrioid variant YST with mature teratoma in the retro-peritoneal specimen.