Cisplatin-based chemotherapy of primary extragonadal germ cell tumors. A single institution experience

Extragonadal germ cell tumors account for only 2-5% of all germ cell neoplasms in adult males. Because these tumors are rare and, in part, biologically distinct from their testicular counterparts, their optimal management continues to be defined.

The medical records of 51 patients with extragonadal germ cell tumors were reviewed. All patients were treated with cisplatin-based chemotherapy at a single institution between 1981 and 1994.

Thirty-five patients had nonseminomatous germ cell tumors and 16 had pure seminomas. Sixteen tumors arose in the mediastinum (12 nonseminomas, 4 seminomas), and 35 in the retroperitoneum (23 nonseminomas, 12 seminomas). Six of 12 patients (50%) with mediastinal nonseminomas survived with no evidence of disease (NED) at 33-137 months (median, 96 months); all had undergone surgery as part of their treatment. Fifteen of 23 patients (65%) with retroperitoneal nonseminomas are alive with NED at 2-145 months (median, 39 months). Fifteen of 16 patients (94%) with extragonadal seminomas survived with NED at 2-141 months (median, 66 months), and 1 patient died from late irradiation-related toxicity. Three patients with retroperitoneal nonseminomas developed a testicular seminoma at 35, 42, and 77 months, respectively; all are currently disease free.

Mediastinal and retroperitoneal nonseminomas have distinct clinical features. As in other series, clinical outcome is somewhat inferior for mediastinal nonseminomas compared with retroperitoneal nonseminomas. Regardless of the site of presentation, the vast majority of patients with extragonadal seminomas can expect cure. It remains controversial, however, whether retroperitoneal germ cell tumors are metastatic from a primary testicular germ cell tumor.