Primary Mediastinal Germ Cell Tumors in Children and Adolescents: Results of the German Cooperative Protocols MAKEI 83/86, 89, and 96

Abstract

PURPOSE: To evaluate children and adolescents with primary mediastinal teratoma and malignant germ cell tumors (GCTs).PATIENTS AND METHODS: Forty-seven patients from the German nontesticular GCT studies were analyzed (median age, 2.5 years; range, neonate to 17 years). Teratoma (n = 21) were resected, and no adjuvant treatment was given. Malignant GCTs (n = 26) were treated with cisplatin-based chemotherapy and resection. Three of 26 patients underwent radiotherapy.RESULTS: In all patients with teratoma, tumor markers were normal. Surgery of teratoma was complete in 17 of 21 patients and microscopically incomplete in four of 21 patients, and we observed no relapse after a median follow-up of 29 months. In 23 of 26 patients with malignant GCTs, alpha-fetoprotein and/or beta-human chorionic gonadotropin were elevated. Twelve of 26 patients received adjuvant chemotherapy after initial resection, which was complete in six of 12 patients, whereas delayed resection after preoperative chemotherapy was complete in 10 of 11 patients (P = .03). Four of six patients underwent second-look thoracotomy after incomplete primary surgery. Three of 26 patients did not undergo tumor resection. The final completeness of resection was the strongest prognostic indicator (event-free survival [EFS], 0.94 ± 0.06 v 0.42 ± 0.33; P < .002). Local stage and distant metastases were not prognostically significant at the .05 level. For all malignant GCTs, the 5-year survival rate was 0.87 ± 0.05 (median follow-up, 51 months), with an EFS of 0.83 ± 0.05.CONCLUSION: The prognosis of mediastinal teratoma is excellent after complete or microscopically incomplete resection. In children with malignant GCT, the prognosis is favorable with a therapeutic strategy of delayed resection after preoperative chemotherapy. In most children, the diagnosis can be based on elevated tumor markers and imaging. Biopsy is indicated in nonsecreting GCT.