Novel Case of Metastatic Testicular Immature Teratoma Invading the Duodenum

We present the first report of an immature teratoma arising from a germ cell testicular cancer invading the duodenum. While other seminomatous and non-seminomatous germ cell tumors are known to metastasize to the duodenum, this is the first such case involving an immature teratoma directly invading the duodenum from a metastatic retroperitoneal mass.