PROTOCOL OUTLINE: Patients receive granulocyte colony-stimulating factor (G-CSF) subcutaneously every day for 8 weeks; nonresponders receive an increased dose for an additional 8 weeks. Patients who respond at week 8 or 16 are then tapered to a lower maintenance dose of G-CSF administered every other day through week 40. The dose is adjusted to maintain an absolute neutrophil count above 1500.