Impact of Pretransplant Salvage Therapies on Outcome of Hodgkin Lymphoma Patients Performing Allogeneic Transplant

Allogeneic transplant is an effective salvage therapy in patients with Hodgkin lymphoma (HL) relapsed or refractory (R/R) to previous treatments. In recent years, immunotherapies (conjugated antibody and checkpoint inhibitors [CPI]) showed interesting results and were used as bridge therapies to allotransplant.The aim of this retrospective study in Lazio region was to evaluate the impact of these new therapies on outcome after allogeneic hematopoietic stem cell transplantation (allo-SCT) in comparison with standard chemotherapies used in the past.We selected all consecutive patients with diagnosis of HL transplanted in four hematology transplant units, and we collected data obtained from patients' records concerning all the treatments before allo-SCT.A total of 56 patients were enrolled in this study. All patients underwent allo-SCT for R/R HL. Seventeen patients (30%) received chemotherapy prior to allo-SCT (group B); they were treated between 2008 and 2015; and 39 patients (70%) received brentuximab vedotin (BV), CPI, or both before allo-SCT as a bridge to transplant (group A); they were treated between 2012 and 2020. Twenty-five patients were treated with BV alone, 2 with CPI alone, and 12 first with BV and then with CPI. No patient received concomitant BV and CPI. At 5 years from allo-SCT, overall survival (OS) was 59% and progression-free survival (PFS) was 65%. No statistical differences in OS or PFS were observed between patients in groups A and B. Relapse was significantly associated with a lower survival. The only factor associated with a reduced risk of relapse was development of any grade acute graft versus host disease (GVHD) (p > 0.02).This regional real-world experience shows the changes that have taken place in the last 10 years in R/R HL using new drugs to render a patient eligible for allo-SCT. This strategy appears to guarantee an impressive disease control with an increased risk of complications, for example, aGVHD, that appear to nullify this advantage at least in part.