Efficacy of ex vivo purging with CD34+selection to maximize the effects of autologous stem cell transplantation in peripheral T-cell lymphoma patients

Background aims: Peripheral T-cell lymphomas (PTCLs) are rare and aggressive tumors with uncertain optimal treatment. This study investigated the clinical outcomes of high-dose chemotherapy (HDT) followed by autologous stem cell transplantation (ASCT) after CD34+ selective purging in PTCL patients. Methods: Retrospective analysis included 67 PTCL patients who achieved remission and underwent HDT/ ASCT. CD34+ selective purging was performed using CliniMACS* (Miltenyi Biotec, Bergisch Gladbach, Germany). Survival outcomes, engraftment, lymphocyte subsets and viral infections were evaluated. Results: CD34+ selective purged autografts were associated with significantly improved overall survival (OS) and disease-free survival (DFS) compared with unpurged autografts (5-year OS, 73.3% versus 37.8%, 5-year DFS, 73.8% versus 33.4%). The cumulative incidence of relapse was also lower in the purged group (31.5% versus 73.3%). Subgroup analysis revealed significant survival benefits in the high-risk group receiving purged autografts. Lymphocyte subset analysis showed increased natural killer (NK) cell counts in the purged group after ASCT. Higher post-ASCT lymphocyte-to-monocyte ratio (LMR) was associated with improved OS and DFS. Conclusions: CD34+ selective purging in PTCL patients undergoing HDT/ASCT improved survival outcomes and reduced relapse risk. The procedure increased NK cell counts and post-ASCT LMR. CD34+ selective purging may minimize autograft tumor cell contamination and enhance efficacy in T-cell lymphomas. (c) 2023 International Society for Cell & Gene Therapy. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)