Forty-four patients with nonseminomatous germ cell tumors with "poor prognostic features" were entered on the VAB-5 regimen and 38 are evaluable. VAB-5 represents an intensified version of the VAB-4 protocol. Poor prognostic features were considered to be bulky metastases (>5 cm in diameter), palpable retroperitoneal disease, liver metastases, brain metastases, involvement of two or more parenchymal organs, pure choriocarcinoma, alpha fetoprotein or human chorionic gonadotropin serum levels over 1000 ng/ml, lactic acid dehydrogenase serum levels over 400 mg/dl, and failure to prior chemotherapy. Eighteen of 38 evaluable patients became free of neoplasm, 11 with chemotherapy alone, and seven with combined chemotherapy and surgery. Fourteen of 18 complete responders remain alive and free of disease with a median follow-up of 50 months. Complete remission with testis tumor occurred in 13/15 without and 5/15 with prior chemotherapy and in none of eight patients with primary extragonadal germ cell tumors. Thirty-one patients received antibiotics when they developed fever during myelosuppression. Ten patients developed transient serum creatinine levels over 2 mg/dl after cis-platinum and one required hemodialysis with subsequent recovery. All patients had severe mucositis after induction. An apparent improvement of results over prior VAB protocols in patients with poor prognostic features was compromised by significant increases in toxicity and such patients require special study to improve cure rates.