Patients receive oral suberoylanilide hydroxamic acid (SAHA) twice daily on days 1-14. Treatment repeats every 21 days for 4 courses in the absence of disease progression or unacceptable toxicity. Patients are then evaluated for disease response. Patients achieving a complete response receive an additional 2 courses of SAHA. Patients achieving stable disease or a partial response receive 4 additional courses of SAHA. After completion of study treatment, patients are followed within 4 weeks.