The impact of external beam radiation therapy prior to autologous bone marrow transplantation in patients with non-Hodgkin's lymphoma

External beam radiation therapy (XRT) is frequently used to treat refractor y disease sites or consolidate remission in patients with relapsed non-Hodg kin's lymphoma (NHL) prior to autologous bone marrow transplantation (ABMT) . We report the long-term outcome and toxicitics associated with this thera py. We uniformly treated 552 patients with NHL with total body irradiation, high-dose chemotherapy, and anti-B-cell monoclonal antibody-purged ABMT. O f these patients, 152 received XRT to the mediastinum, abdomen, or pelvis ( n=102) or other sites (n=50) prior to ABMT. In this nonrandomized series, t here was no difference in progression-free survival between patients treate d with. XRT and those not treated with XRT. For patients with indolent hist ology, there was no difference in overall survival between patients treated with XRT and those not treated with XRT. For patients with aggressive hist ology, the median overall survival time was 64 months in the XRT patients a nd 79 months in the patients not treated with XRT (P=.09). The risk of acut e transplantation-related deaths was not influenced by prior XRT (P=.68). O f patients who received XRT, 12.5% developed secondary myelodysplasia compa red with 5.8% of patients not receiving XRT (P=.01). Patients receiving XRT to the mediastinum. or axilla had a significantly higher risk of late resp iratory death (P=.002). In conclusion, XRT allows refractory patients to be come eligible for transplantation and experience a disease-free survival in terval equivalent to that of patients who do not receive XRT. However, a hi gher incidence of non-relapse-associated deaths was observed in patients wh o received XRT. Future work should explore alternative conditioning strateg ies and altered timing of XRT, in an attempt to limit these late toxicities .