DISEASE CHARACTERISTICS: Histologically or cytologically proven germ cell tumor Seminoma or nondysgerminoma origin Gonadal (testicular or ovarian) OR Extragonadal OR Retroperitoneal OR Primitive mediastinal AFP elevated and/or HCG greater than 200 mIU/mL No growing teratoma Refractory disease to any treatment line Refractory disease is defined by the elevation of AFP and/or HCG during the chemotherapy Refractory to treatment line consisting of one conventional dose of cisplatin (dose intensity greater than 33 mg/m2/week) OR at least 1 month since last course of chemotherapy with or without increase in the size of measurable lesions OR Received 2 regimens of conventional chemotherapy, typically the following: Bleomycin, etoposide, and cisplatin: 3-4 courses* OR Etoposide and cisplatin: 4 courses* AND Vinblastine, etoposide, ifosfamide, cisplatin: 4 courses of 3 week regimen (as standard salvage chemotherapy)* * Unless patients could be treated with a first line conventional treatment OR a first salvage conventional treatment especially patients who could be treated with T93 good prognosis protocol or T93 bad prognosis protocol or IT94 protocol Bidimensionally measurable disease OR Significant elevation of tumor markers: HCG, free beta-HCG, AFP OR Evaluable disease plus increase in tumor markers No germ cell CNS tumors or clinically significant CNS metastases

PATIENT CHARACTERISTICS: Age: Over 15 Performance status: ECOG 0-2 Life expectancy: Greater than 3 months Hematopoietic: WBC greater than 3,000/mm3 AND Platelet count greater than 150,000/mm3 Hepatic: Bilirubin less than 1.5 times normal SGOT/SGPT less than 2 times upper limit of normal (ULN) Alkaline phosphatase less than 2 times ULN Gamma glutamyl transferase less than 2 times ULN Renal: Creatinine less than 1.4 mg/dL Creatine clearance greater than 60 mL/min Cardiovascular: No cardiac insufficiency LVEF at least 50% Other: HIV negative No other malignancy except basal cell skin cancer

PRIOR CONCURRENT THERAPY: Biologic therapy: Not specified Chemotherapy: See Disease Characteristics No prior intensive chemotherapy with stem cell support Endocrine therapy: Not specified Radiotherapy: Prior prophylactic anterior irradiation of the diaphragm for stage I seminoma allowed Surgery: Not specified