R-CHOP-14R-HIDAC,followed by RIT/HDT/ASCR.
OtherINDUCTION: R-CHOP-14 CHEMOTHERAPY: 4 cycles every 2 weeks ± 1 day All patients in the study in both phases will undergo induction and consolidation with R-CHOP 14R-HIDAC, followed by RIT/HDT/ASCR. Patients will undergo restaging scans 12 to 14 days following completion of R-CHOP 14, with CT, and FDG-PET. Patients demonstrating at least a PR may proceed to consolidation with R-HIDAC. CONSOLIDATION: R- HIDAC CHEMOTHERAPY: 2 cycles every 3 weeks ± 2 days After R-HIDAC, restaging will occur 17-21 days post cycle 2 with CT scan (or FDG-PET, if this was positive following R-CHOP-14). Radioimmunotherapy Dosimetric dose is given approximately 4-5 weeks after completing cycle 2 of R-HIDAC. This is to be preferred 1 week post restaging scans 17-21 days post cycle 2 of RHIDAC, and up to 2 weeks post-scans will be acceptable only if required by 131 I Tositumomab availability.
Other names: HIGH DOSE CHEMOTHERAPY AND AUTOLOGOUS STEM CELL RESCUE (ASCR)Patients admitted to the hospital for high dose chemotherapy. The anticipated length of, stay is 3-4 weeks. 14 days ± 1 day following the administration of the therapeutic dose of Iodine 131 I, Tositumomab, patients will be admitted for high-dose chemotherapy. BEAM, will be administered