The Role of Autologous Stem Cell Transplantation in the Treatment of Diffuse Large B‐cell Lymphoma in the Era of CAR‐T Cell Therapy

For many years now and based on the results of the PARMA trial, relapsed Diffuse Large B‐cell Lymphoma (DLBCL) is treated with salvage combination cytotoxic chemotherapy (most often platinum‐based) followed by high dose myeloablative chemotherapy and autologous stem cell transplantation (auto‐HCT). This approach has resulted in long‐term disease free survival in about half of the patients. With the incorporation of rituximab in the upfront treatment (RCHOP), more patients with DLBCL are cured but there has been a signal of inferior outcomes with auto‐HCT if DLBCL relapses. Nevertheless, a careful review of the literature still shows very good outcomes with auto‐HCT for DLBCL with complete remission to salvage chemotherapy. For those who do not respond well to classic salvage other approaches are reviewed here including chimeric antigen receptor (CAR) T‐cell therapy and treatment with antibody‐drug conjugates (ADCs) as well as bispecific T‐cell engagers (BiTEs). The outcome of auto‐HCT after successful treatment with ADCs or BITEs is unknown. It is also unknown if CAR‐T cell therapy should be reserved for those who have failed 2 lines of chemotherapy or it should be moved earlier. Finally, we review here the effects of Myc and bcl2 amplifications or translocations to the outcome of the auto‐HCT. Some attempts to improve the salvage or conditioning regimens are mentioned. We also discuss the role of allogeneic stem cell transplantation (allo‐HCT) in the paradigm of treatment for relapsed DLBCL.