Germ cell tumors of the mediastinum. A 30-year experience

The records of 98 consecutive patients (58 males and 40 females; median age, 27 years; age range, 2-64 years) who presented with a primary germ cell tumor (GCT) of the mediastinum between January 1960 and December 1990 were reviewed. There were 45 mature teratomas, 8 immature teratomas, 16 pure seminomas, and 24 malignant nonseminomatous GCT (MNSGCT).

All patients with mature teratomas were cured by radical resection alone, except one patient who died intraoperatively. Among the eight patients with immature teratomas, five were treated before the advent of cisplatin treatment (two children younger than 15 years were cured by surgery alone and three adults died within 7 months after operation). Three patients underwent surgery followed by cisplatin-based chemotherapy (two are still alive and one died of an associated rhabdomyosarcoma). Thirteen of 16 patients with seminomas (81%) were cured by surgery either alone (5 patients) or with adjuvant radiation therapy (8 patients). Among the 24 MNSGCT, 10 were treated before 1980 without cisplatin and all but 1 died of disease progression. Fourteen patients were treated by initial high-dose cisplatin combination chemotherapy and 8 (57%) achieved complete remission (2 died of systemic mastocytosis development).

Results indicate the benignity of mature teratomas of the mediastinum, the age-dependent clinical course of immature teratomas, and the excellent prognosis of seminomas. The improved survival advantage resulting from cisplatin-based chemotherapy in MNSGCT is impaired by the propensity to nongerminal solid tumor development and hematologic malignancies.