- Harvest: Autologous or syngeneic bone marrow or peripheral blood stem cells (PBSC) are harvested. Patients undergoing PBSC collection receive filgrastim (G-CSF) beginning 2-3 days prior to collection and continuing through the end of collection. For patients without bone marrow involvement at diagnosis, autologous bone marrow or PBSC are harvested after completion of 1-2 courses of induction therapy. For patients with bone marrow involvement at diagnosis, bone marrow or PBSC are harvested after completion of 4 courses of induction therapy, surgery, and completion of 1 course of MOAB 3F8, if bone marrow is in remission. If a patient's bone marrow/PBSC cannot be collected or harvested after completion of induction therapy because of hypoplasia or persistent tumor, bone marrow/PBSC collected or harvested before starting protocol or syngeneic bone marrow/PBSC may be used. If neither of these options is available, patients who do not clear marrow by course 5 have the option of proceeding directly to the posttransplantation therapy phase below, while delaying transplantation until bone marrow is clear.