STEM CELL MOBILIZATION FOR CELL COLLECTION: Patients receive filgrastim subcutaneously (SC) twice daily (BID) for 5-6 days (on days 1-6 of mobilization). Patients receive plerixafor SC once daily (QD) on days 4-6 of mobilization. Peripheral blood stem cell (PBSC) count will be checked daily starting on day 4 of mobilization. Patients who have a PBSC count of >= 5 CD34+ cells/mcL will undergo up to 2 apheresis collections on consecutive days.