Propensity Score-Matched Analysis Supports the Survival Benefits of Combination Chimeric Antigen Receptor T-Cell Therapy with Autologous Transplantation in Relapsed or Refractory Diffuse Large B-Cell Lymphoma: Insights from a Real-World Study in China.

Chimeric antigen receptor T-cell (CAR-T) therapy has markedly improved lymphoma outcomes. However, real-world data evaluating the survival benefit of CAR-T therapy combined with autologous stem cell transplantation (ASCT) in unselected patients are still limited. The efficacy and survival outcomes of ASCT combined with CAR-T therapy versus CAR-T monotherapy in relapsed or refractory diffuse large B-cell lymphoma (DLBCL) were assessed. This observational, retrospective study included 171 patients with DLBCL hospitalized at the First Affiliated Hospital of Soochow University from June 2017 to December 2023. Patients were grouped according to treatments they had received in routine care: (1) ASCT combined with CAR-T therapy (ASCT+CAR-T, n = 70) and (2) CAR-T monotherapy (CAR-T alone, n = 101). Multivariable Cox regression models were used to estimate hazard ratios (HRs) for death and disease progression. A 1:1 propensity score matching was utilized to control for potential confounders in this real-world study. Before matching, the ASCT+CAR-T group had significantly higher objective response rates (ORRs) (87.14% versus 70.30%, P = .010) and complete response (CR) rates (62.86% versus 36.63%, P < .001) compared with the CAR-T group. After a median follow-up time of 35.63 months (95% CI: 30.07 to 41.30), overall survival (OS) was significantly improved in the ASCT+CAR-T group compared with the CAR-T group (HR = 0.433, 95% CI: 0.255 to 0.734, log-rank P = .001). Progression-free survival (PFS) showed a similar advantage (HR = 0.531, 95% CI: 0.336 to 0.840, log-rank P = .006). After 1:1 propensity score matching, CR rates remained significantly higher in the ASCT+CAR-T group compared with the CAR-T group (61.54% versus 40.38%, P = .031). However, the ORRs between groups (ASCT+CAR-T: 90.38% versus CAR-T: 78.85%, P = .103) were not statistically significant. The median follow-up time was 36.00 months (95% CI: 27.53 to 73.30) and 37.80 months (95% CI: 30.07 to 50.40) in the ASCT+CAR-T group and CAR-T group, respectively. OS remained superior in the ASCT+CAR-T group compared with the CAR-T group (HR = 0.486, 95% CI: 0.252 to 0.936, log-rank P = .028). The PFS benefit also persisted (HR = 0.558, 95% CI: 0.315 to 0.987, log-rank P = .042). ASCT+CAR-T did not increase non-relapse mortality, and rates of grade ≥3 CRS and ICANS were comparable to CAR-T alone. ASCT combined with CAR-T therapy was associated with improved survival and higher remission rates compared to CAR-T alone. These findings support the potential of ASCT combined with CAR-T therapy as a favorable therapeutic approach for controlling relapsed or refractory DLBCL.