OUTLINE: This is a dose-escalation study. Patients are stratified according to serum level of anti-DTGM antibody titer (2 mg/L or less vs greater than 2 mg/L). Patients receive DTGM fusion protein IV over 15 minutes on days 1-5. Patients with a partial response are eligible for retreatment. Cohorts of 3-6 patients receive escalating doses of DTGM fusion protein until the maximum tolerated dose (MTD) is determined. The MTD is defined as the dose preceding that at which 2 of 3 or 2 of 6 patients experience dose-limiting toxicity. Once the MTD is determined, additional patients are accrued to receive treatment with DTGM fusion protein at the MTD. Patients are followed monthly until disease progression.