OBJECTIVES:~Primary~Determine the progression-free survival of older patients with relapsed or refractory non-Hodgkin's lymphoma treated with iodine I 131 tositumomab followed by autologous stem cell transplantation.~Secondary~Determine the overall survival of patients treated with this regimen.~Determine the toxicity and tolerability of this regimen in these patients.~OUTLINE:~Radioimmunotherapy: Patients receive a test dose of iodine I 131 tositumomab on day -24 to determine biodistribution. Patients then receive therapeutic iodine I 131 tositumomab IV over 1 hour on day -14 and are entered into radiation isolation until day -4.~Autologous stem cell transplantation: Patients undergo autologous bone marrow or peripheral blood stem cell transplantation on day 0. Patients undergoing bone marrow transplantation receive filgrastim (G-CSF) or sargramostim (GM-CSF) subcutaneously beginning on day 0 and continuing until blood counts recover.~Patients are followed at 1, 3, 6, and 12 months and then annually thereafter.~PROJECTED ACCRUAL: A total of 24-30 patients will be accrued for this study within 2 years.
RATIONALE: Radiolabeled monoclonal antibodies, such as iodine I 131 tositumomab, can locate cancer cells and deliver radioactive cancer-killing substances to them without harming normal cells. Combining a radiolabeled monoclonal antibody with autologous stem cell transplantation may be an effective treatment for non-Hodgkin's lymphoma.~PURPOSE: Phase II trial to study the effectiveness of combining iodine I 131 tositumomab with autologous stem cell transplantation in treating older patients who have relapsed or refractory non-Hodgkin's lymphoma.