Prognostic differences of refractory/relapsed nodal and extranodal diffuse large B-cell lymphoma in the chimeric antigen receptor T cell therapy era.

Background: Extranodal involvement is recognized as a poor prognostic factor for diffuse large B-cell lymphoma (DLBCL). However, the prognostic differences of patients with refractory/relapsed (R/R) nodal and extranodal DLBCL in the chimeric antigen receptor T cell (CART) therapy era are still unclear.

Methods: In this study, 18 R/R nodal DLBCL (R/R N-DLBCL) and 19 R/R extranodal DLBCL (R/R EN-DLBCL) were enrolled to compare clinical outcomes.

Results: The median follow-up time was 13 (range, 1-47) months and one-year progression-free survival (PFS; 83.3% vs. 42.1%, P = 0.008) and one-year overall survival (OS; 94.4% vs. 63.2%, P = 0.020) were significantly different between nodal and extranodal patients. In the multivariable Cox regression analysis, R/R EN-DLBCL was associated with worse PFS (hazard ratio [HR] = 4.263, P = 0.018) and OS (HR = 9.589, P = 0.034) compared to R/R N-DLBCL. Additionally, autologous hematopoietic stem cell transplantation (ASCT) combined with CART therapy (ASCT + CART) was correlated with better PFS (HR = 0.164, P = 0.003) compared to CART treatment alone.

Conclusions: The clinical outcomes of R/R EN-DLBCL were worse than R/R N-DLBCL in patients receiving CART therapy and ASCT + CART therapy is a promising alternative treatment for patients with R/R EN-DLBCL.