Outcomes of Autologous and Allogeneic Stem Cell Transplantation in FL

Follicular lymphoma (FL) is an indolent malignancy characterized by frequent relapses. While chemo-immunotherapy remains effective for most patients, those with aggressive disease or early relapses may require hematopoietic stem cell transplantation (HSCT). A study presented at ASH 2024 analyzed outcomes for autologous (ASCT) and allogeneic (allo-HSCT) transplants reported to the European Society for Blood and Marrow Transplantation registry from 2010 to 2022, excluding patients with aggressive transformation.

Among 7,330 patients with ASCT, the median age was 57 years, with 58% male and 86% having received prior rituximab. At transplant, 53% were in complete response (CR), 37% in partial response (PR), and 10% had stable or progressive disease (SD/PD). The majority underwent BEAM conditioning (66%), and 99% received peripheral blood stem cells (PBSC). At a median follow-up of 3.2 years, 3-year overall survival (OS) was 81%, progression-free survival (PFS) 55%, relapse incidence (RI) 41%, and non-relapse mortality (NRM) 5%. At 10 years, OS declined to 58% and PFS to 37%.

For 1,901 patients with allo-HSCT, the median age was 54 years, with 62% male and 53% having relapsed after ASCT. Reduced-intensity conditioning (RIC) was used in 72%, with PBSC sourced from matched unrelated donors (57%), siblings (34%), or haploidentical donors (8%). At a median follow-up of 5.2 years, 5-year OS was 59%, PFS 51%, RI 20%, and NRM 30%. Acute graft-versus-host disease (aGVHD) occurred in 30% of cases (grade 2-4) at day 100, and extensive chronic GVHD was 17% at 2 years. At 10 years, OS, PFS, and GVHD-free, relapse-free survival (GFRFS) were 51%, 44%, and 29%, respectively.

Multivariate analysis indicated worse OS with older age, PR/SD/PD status, and use of haploidentical or unrelated donors. However, TBI-based conditioning improved outcomes in RIC recipients.

Researchers noted that the study confirmed the efficacy of HSCT for FL and provides a benchmark for evaluating emerging therapies like CAR-T cells and bispecific antibodies.

Reference:

Serroukh YIM, Fekom M, Khvedelidze I, et al. Outcome of hematopoietic stem cell transplantation for follicular lymphoma, a benchmark study from the lymphoma working party of the European Society for Blood and Marrow Transplantation. Abstract 749. Presented at ASH 2024. San Diego, California.