OUTLINE: Patients are stratified according to prior chemotherapy (yes vs no). Patients receive induction interleukin-12 IV over 5-20 seconds on day -13 and then daily on days 1-5. Treatment continues every 21 days in the absence of unacceptable toxicity or disease progression. Patients are followed every 3 months for 2 years, every 6 months for 3 years, and then annually thereafter.