OUTLINE: Patients receive pyrazoloacridine IV over 3 hours every 3 weeks. The minimum treatment period is 2 courses with tumor restaging at 6 weeks. Patients with complete remission (CR) or partial remission (PR) may continue on treatment until refractory (PR) or for at least 3 additional courses (CR). Patients with stable disease continue on therapy for at least 2 more courses. Patients are followed until death.