Placental site trophoblastic tumor in a late recurrence of a nonseminomatous germ cell tumor of the testis.

Placental site trophoblastic tumor (PSTT) is a well-defined entity in the female genital tract. In the male genital tract, a single case of PSTT in the testis of a young boy has been reported. Despite its very rare occurrence, PSTT of the testis has been incorporated in the latest WHO classification of tumors of the male genital tract. In this article, a case of a PSTT in a late retroperitoneal recurrence of a testicular nonseminomatous germ cell tumor in an adult male patient is presented. The tumor was discovered due to an elevated serum level of beta-human chorionic gonadotropin 4 years after chemotherapy. Upon review of the primary testicular tumor, small foci of intermediate trophoblastic tumor cells were discerned. This case illustrates that tumor cells resembling intermediate trophoblastic cells may metastasize to regional retroperitoneal lymph nodes. Because of their resistance to chemotherapy, these cells may invade surrounding tissue in due time, acquiring the typical morphology of PSTT.