OUTLINE: This is a dose escalation study of fludarabine. Patients receive radiotherapy on days 1-5 for 7 weeks. Patients receive fludarabine IV on days 1-5 of weeks 6 and 7 of radiotherapy. Fludarabine is administered 3-4 hours prior to daily radiotherapy. Cohorts of 3 patients receive escalating doses of fludarabine until the maximum tolerated dose (MTD) is determined. The MTD is defined as the dose that produces a severe toxicity rate nearest to 20%. Patients are followed every 4 weeks after the completion of treatment until acute reactions have resolved, then every 3 months for 2 years, every 4 months for 1 year, and then every 6 months for 2 years.