- Stem cell mobilization and collection: Patients receive filgrastim (G-CSF) subcutaneously (SC) beginning on day 5 and continuing until stem cell collection is completed. Patients undergo a maximum of 5 daily apheresis sessions. Patients who mobilize fewer than the required minimal number of stem cells repeat apheresis with high-dose G-CSF alone or undergo bone marrow harvest. Patients then proceed to radiotherapy, high-dose chemotherapy (HDC), and autologous stem cell transplant (ASCT) OR noncross-resistant chemotherapy based on response to ICE-based cytoreductive chemotherapy.