Therapy with high-dose carboplatin plus etoposide-based chemotherapy plus autologous bone marrow rescue (AUBMR) was administered to 29 patients with advanced germ cell tumors (GCT) refractory to cisplatin-based chemotherapy. Two groups of patients with refractory disease were treated. Sixteen patients had been identified as "poor risk" at diagnosis and had an inappropriately slow decline of serum tumor markers after two cycles of induction cisplatin-based therapy (Group A). In addition, 13 patients were treated who had never had a complete response (CR) or had relapses after ifosfamide-based salvage chemotherapy (Group B). Patients in Group A were treated with high-dose carboplatin etoposide, and patients in Group B received high-dose carboplatin, etoposide, and cyclophosphamide. Fifteen of 29 (52%) patients had a CR (9, Group A; 6, Group B). The patients in Group A had fewer hematologic toxic effects, and the median number of days from day 0 to a granulocyte count greater than 0.5/microliters was 16 and to a platelet count of more than 50/microliters was 15, compared with 22 days and 23 days in Group B, respectively. There were fewer episodes of culture-positive sepsis in Group A (12%) compared with Group B (26%), and the only treatment-related death occurred in Group B. Therapy with high-dose carboplatin plus etoposide-based chemotherapy plus AUBMR is effective for patients with GCT refractory to regimens of cisplatin with or without ifosfamide. Early use of high-dose chemotherapy reduces hematologic toxic effects and allows patients to start treatment in a more predictable fashion after cytoreduction, rather than when the disease is progressing rapidly.