Comparative outcomes of CAR-T cell therapy with and without autologous stem cell transplant consolidation in diffuse large B-cell lymphoma: A real-world propensity-matched analysis

Abstract Background: CAR-T cell therapy has transformed the treatment landscape of diffuse large B-cell lymphoma (DLBCL). Autologous stem cell transplant (ASCT) has long been a cornerstone in DLBCL management. However, the benefit of consolidative ASCT after CAR-T remains unclear. Methods: Using TriNetX, adults (≥18 years) with DLBCL treated with tisacel, lisocel or axicel were identified. Cohort 1 was CAR-T alone; Cohort 2 was CAR-T followed by ASCT. Propensity score matching yielded 560 patients per cohort. Outcomes included overall survival (OS), remission, myelodysplastic syndrome (MDS), acute myeloid leukemia (AML), ICU admission, and hospitalization. Results: Median follow-up was 430 vs. 633 days (CAR-T vs. CAR-T→ASCT). OS risk was 30.4% vs. 36.0%, risk difference (RD) –5.7% (95% CI –11.2 to –0.2; p=0.044), median OS 1824 vs. 1484 days (HR 1.10; 95% CI 0.90–1.36; p=0.34). Remission rates were similar (RD –0.9%, 95% CI –3.2 to 1.5; p=0.47). MDS incidence was higher with ASCT (RD –3.0%, 95% CI –5.3 to –0.7; p=0.01), while AML was similar (p=0.18). ICU admission RD was 3.0% (95% CI –1.6 to 7.5; p=0.20) but HR 1.47 (95% CI 1.05–2.07; p=0.025). Hospitalization RD was 7.7% (95% CI –0.1 to 15.4; p=0.072) but HR 1.99 (95% CI 1.05–3.80; p=0.020). Conclusions: ASCT after CAR-T in DLBCL did not improve OS and was associated with increased MDS incidence and higher ICU and hospitalization hazards. Further clinical trials should be designed and studied.