Long-Term Outcome of Autologous Stem Cell Transplantation (ASCT) for Hodgkin Lymphoma (HL) in the ABVD Therapeutic Era.

Abstract

ASCT is the standard therapy for relapsed HL. However, the majority of published studies suggesting benefit of ASCT for relapsed HL include relatively young patients (pts) with favorable prognostic features, and have relatively short follow-up. Moreover, very little data exists on the outcome of pts who experience progression of HL after ASCT. To determine the long-term outcome of ASCT in the modern, “ABVD-era”, and the impact of allogeneic transplantation in pts who fail ASCT, we reviewed all pts with HL who were treated with ASCT between 1990 and 2005 at the University of Rochester. 117 pts (44% female; 89% Caucasian) with documented HL were treated with ASCT for relapsed or refractory HL. At ASCT, median age was 34 years (range 19–66). 75% of these pts were treated initially with ABVD or MOPP-ABVD hybrid therapy. Histology was: NS (n=82), mixed cellularity (n=20), LP (n=6), LD (n=3), and classical NOS (n=6). 32% of pts had relapsed within 1 year of initial therapy, and 25% were refractory to therapy prior to ASCT. Conditioning regimens at ASCT were BEAC (n=80); BEAM (n=28); CBV (n=1); Cy/TBI (n=8). 49% of pts received XRT following ASCT. Median follow-up of entire cohort exceeded 5 years. At 5 years, overall survival (OS) for entire population was 50%, and event-free survival (EFS) was 38%. As expected, pts older than 45 yrs of age (n=21, p=0.06) and pts who relapsed within 1 year of initial therapy (p=0.0004) had an inferior OS after ASCT. In total, 49 pts have died; of these, 30 pts died of HL. 19 deaths occurred in remission: 9 were conditioning-related within the first 100 days of ASCT; 3 were from secondary malignancies (2 AML, 1 NHL), 1 from colitis, 1 from pulmonary fibrosis, and 5 with unknown cause. 9 of the deaths occurred more than 5 yrs after ASCT. 54 pts had progression of HL post ASCT; median survival for this group was 2.1 years after ASCT. 14 of these pts (26% of pts who failed ASCT) underwent allogeneic transplantation. 8 of these patients have died: 5 from progression of HL, 2 from pulmonary toxicity, and 1 from GVHD. Of the 5 remaining pts, 1 has progression of HL after allogeneic transplantation, and 3 have chronic GVHD. We conclude that ASCT remains a curative option for patients relapsing after ABVD, as there is a clear plateau on the relapse free survival curve after 5 years. Primary refractory disease and older age at ASCT dramatically affects outcome. In this modern era, deaths in remission after ASCT remain a significant problem due to both short-term and long-term toxicities of therapy. The risk of progression of HL persists until 5 years after ASCT, emphasizing the importance of prolonged follow-up. Although some pts who progress with HL after ASCT may live for years with a seemingly indolent form of HL, there is no plateau on the survival curve, and the majority of pts who progress after ASCT are not alive 2 years post ASCT. Allogeneic transplantation has not yet had a significant impact on OS for this group of pts. Novel approaches are clearly needed for the majority of pts who progress after ASCT, particularly older patients at ASCT and patients with primary induction failure.