Patients receive induction chemotherapy consisting of doxorubicin IV over 5 minutes, bleomycin IV over 10 minutes, vinblastine IV over 5 minutes, and dacarbazine IV over 15-30 minutes on days 1 and 15. Treatment repeats every 28 days for 5 courses in the absence of disease progression or unacceptable toxicity. Patients who show at least partial response after the fifth course of induction chemotherapy and whose blood counts have recovered are randomized to 1 of 2 treatment arms.