- Second PBSC mobilization with chemotherapy: Patients not meeting the collection goal receive cyclophosphamide IV over 2 hours on day 1 and G-CSF SC beginning on day 4 and continuing until stem cell collection is complete. Patients meeting the collection goal after PBSC mobilization via G-CSF alone or in combination with chemotherapy will undergo tandem autologous transplantation. If collection goal is not met but the patient has collected > or = 2 x 10^6 CD34 cells/kg, a single autologous transplant will be performed.