Beginning 14 days after the autologous stem cell transplant, patients receive daily subcutaneous injections of sargramostim (GM-CSF) on days 1-7 and daily intravenous interleukin-2 on days 3-7, followed by 1 week of rest. Patients then receive a subcutaneous injection of interferon alfa three times a week for 3 weeks followed by one more week of rest. Treatment is repeated for four courses.