PRIMARY PURE TERATOMA OF THE TESTIS

Purpose: Despite its histologically benign appearance, primary pure te ratoma of the testis is believed to have metastatic potential and beha ve similarly to other nonseminomatous germ cell tumors. We present our experience with the natural history and management of pure teratoma. Materials and Methods: We reviewed the histological findings and clini cal history of 15 patients with primary pure teratoma who were treated during a 15-year period, accounting for 4.2% of all nonseminomatous g erm cell tumors treated during the same period. Fourteen patients were available for followup and are included in this report. Results: In 8 patients the tumor was composed entirely of mature teratoma and in 6 immature elements,were also present, although this finding was not ass ociated with an increased frequency of metastatic disease. Carcinoma i n situ was found adjacent to the tumor in 12 cases. Of 10 patients wit h stage I disease at presentation who were entered on a surveillance p rogram only 2 have had; relapse. The remaining 4 patients had metastat ic disease at presentation and, thus, metastatic disease occurred in a total of 6 of the 14 patients (43%) with a median followup of 46 mont hs (range 5 to 197). Metastatic disease was confined to the retroperit oneum in all 6 patients and only 2 patients had elevated serum marker levels. Five patients were treated with primary chemotherapy followed by resection of a residual mass and in all eases teratoma was identifi ed in the resected mass. One patient underwent primary surgical excisi on of a retroperitoneal mass, which contained teratoma and yolk sac tu mor, followed by chemotherapy. All patients are alive without evidence of progressive disease. Conclusions: In patients with primary pure te ratoma of the testis metastatic disease may develop rand the metastase s may contain other subtypes of nonseminomatous germ cell tumors in ad dition to teratoma. There is probably a reduced frequency of relapse, which should be considered when advising patients with stage I disease , but otherwise management should be the same as for other testicular nonseminomatous germ cell tumors and the prognosis should be excellent .