Comparison of conditioning regimens used for autologous stem cell transplantation in lymphoma

In patients with relapsed or refractory lymphoma, autologous stem cell transplantation (ASCT) following high-dose chemotherapy has become a standard treatment approach for achieving long-term remission and improving overall survival. Conditioning regimens administered prior to ASCT aim to eliminate residual malignant cells and prepare the bone marrow for transplantation, and the efficacy and toxicity profiles of these regimens directly affect patient prognosis. In this study, the clinical efficacy, toxicity profiles, engraftment times, and their effects on progression-free and overall survival of BEAM, CBV, and BuCyE conditioning regimens used in lymphoma patients undergoing ASCT between 1998 and 2023 at the Adult Bone Marrow Transplantation Unit of Eskişehir Osmangazi University Faculty of Medicine Hospital were comparatively evaluated. A total of 124 lymphoma patients who underwent ASCT were included in the study. Of these patients, 91 (73.4%) received BEAM, 23 (18.5%) CBV, and 10 (8.1%) BuCyE conditioning regimens. The median progression-free survival was 30.5 months in the BEAM group, 12.5 months in the BuCyE group, and 171.1 months in the CBV group, with a statistically significant difference observed among the groups. In univariate and multivariate Cox regression analyses, age, conditioning regimen, and pre-transplant remission status were identified as independent prognostic factors for progression-free survival; the CBV regimen was shown to significantly reduce the risk of relapse compared with the BEAM regimen. In analyses of overall survival, prolonged neutrophil and platelet engraftment times were associated with an increased risk of mortality, and prolonged neutrophil engraftment time was identified as an independent adverse prognostic factor for overall survival. In addition, patients who failed to achieve complete response at day 100 after transplantation had a markedly increased risk of mortality.