OUTLINE: This is a dose escalation study. Patients receive interleukin-2 (IL-2) subcutaneously on days 1-7, 9-14, and 16-22. On days 8 and 15, patients receive IL-2 IV over 2 hours. Treatment repeats every 28 days for up to 4 courses in the absence of disease progression or unacceptable toxicity. Cohorts of 6-9 patients receive escalating doses of IL-2 until the maximum tolerated dose (MTD) is determined. The MTD is defined as the dose preceding that at which 2 of 6 or 2 of 9 patients experience dose-limiting toxicity. Patients are followed every 6 months for 4 years and then annually thereafter.