OUTLINE: This is a dose escalation study. Patients receive B43-genistein immunoconjugate IV over 1 hour on days 1-3, 8-10, and 15-17. Treatment continues every 3 weeks in the absence of unacceptable toxicity or until disease progression. Cohorts of 3-6 patients receive escalating doses of B43-genistein immunoconjugate until the maximum tolerated dose (MTD) is determined. The MTD is defined as the dose preceding that at which 2 of 6 patients experience dose limiting toxicity. Patients are followed every 6 months.