Primary germ cell tumors in the mediastinum: a 50-year experience at a single Japanese institution.

BACKGROUND: Primary germ cell tumors (GCT) of the mediastinum share similar clinical and biologic characteristics, which are different from their testicular counterpart. The purpose of the current study was to review the authors' institutional experience of mediastinal GCT, emphasizing the clinical spectrum, time trends of treatment, and recent advances in therapeutic modalities for malignant GCT.

METHODS: Between 1951 and 2000, 129 patients (70 males and 59 females) underwent surgical treatment for GCT, which accounted for 16.0% of the mediastinal tumors during the same period. There were 95 patients with mature teratomas, 13 patients with seminomas, and 21 patients with nonseminomatous germ cell tumors (NSGCT) with median ages of 26.4 years, 27.6 years, and 28.5 years, respectively.

RESULTS: Adult patients with mature teratomas were less symptomatic (33.3%) than pediatric patients (52.4%). All patients with mature teratoma were cured by resection alone. Eight of the 13 patients (61.5%) with seminoma were symptomatic and 10 of 13 patients (83.3%) survived after surgery and radiation with/without chemotherapy. Nineteen of 21 patients (90.5%) with NSGCT had dyspnea, chest pain, and superior vena cava syndrome. Before 1985, patients received radical resection and/or chemoradiotherapy. However, all patients died due to disease progression, with a median survival period of 7.6 months. After 1986, six of eight patients received cisplatin-based chemotherapy, including three who received additional high-dose chemotherapy with a supporting peripheral blood stem cell transplantation until tumor markers normalized. Five patients who underwent salvage resection are currently disease free with a median survival period of 58.3 months.

CONCLUSIONS: The institutional experience indicates the benign nature of mediastinal mature teratomas and the excellent prognosis for patients with seminomas after resection. An improved survival advantage was ensured with cisplatin-based preoperative chemotherapy in patients with NSGCT.