Patterns of Utilization and Outcomes of Autologous Stem Cell Transplantation and Chimeric Antigen Receptor T-Cell Therapy in Relapsed or Refractory Diffuse Large B-cell Lymphomas with MYC and BCL2 and/or BCL6 Rearrangements

Abstract

Background: Patients with Diffuse Large Bcell Lymphoma (DLBCL) with MYC and BCL2 and/or BCL6 gene rearrangements [double-hit lymphoma/triple-hit lymphoma (DHL/THL)] have poor prognosis in the relapsed/refractory setting.

Methods: We utilized a real-world deidentified database of DLBCL patients and report patterns of therapy utilization in relapsed/refractory DLBCL. We used log-rank test to compare real-world overall survival (rwOS) among DHL and non-DHL subgroups for CAR Tcell therapy or ASCT respectively, stratified for prior lines of therapy.

Results: Of all 7,877 patients with DLBCL, 367 patients had DHL while 6113 had non-DHL. Second line chemotherapy was administered to 147 DHL patients and 1517 non-DHL. 1393 were excluded, including 934 with unknown DHL/THL status. Approximately 47% received salvage intent chemotherapy in the DHL subgroup, of which 19% patients eventually received ASCT, while 34% received salvage intent chemotherapy in the non-DHL/THL group with 32% receiving ASCT. DHL/THL status negatively influenced median rwOS for patients who underwent ASCT in the second-line while it was associated with numerically inferior but without statistically significant rwOS among patients that underwent CAR Tcell therapy on multivariable analysis.

Conclusion: rwOS of relapsed DHL/THL is inferior to non-DHL/THL. Fewer patients with DHL/THL were able to proceed with ASCT after salvage chemotherapy compared to non-DHL/THL. ASCT as second-line therapy for relapsed DHL/THL had worse rwOS than for non-DHL/THL, consistent with the natural history of DHL/THL. This difference was not seen for CAR Tcell therapy, which combined with promising results from clinical trials, suggests a greater role for CAR T-cell therapy in relapsed/refractory DHL.