Autologous (auto) versus matched sibling donor (MSD) or matched unrelated donor (MUD) allogeneic (allo) hematopoietic cell transplantation (HCT) in follicular lymphoma (FL) patients (pts) with early chemoimmunotherapy failure (ECF): A Center for International Blood and Marrow Transplant Research (CIBMTR) analysis.

Abstract

7508 Background: Contrary to most FL, high-risk FL pts with ECF (i.e. relapse within 2 yrs of frontline chemoimmunotherapy) have a 5 yr OS of only 50%. (Casulo, JCO 2015). We used the CIBMTR database to compare autoHCT versus either MSD or MUD alloHCT as the first transplant approach in FL pts with ECF. Methods: Adult FL pts (age ≥18) undergoing autoHCT or alloHCT between 2002-2014 and receiving first line rituximab-based chemoimmunotherapies with evidence of ECF (defined as disease relapse or progression within 2 yrs of treatment initiation) were included. The primary endpoint was OS; secondary endpoints were progression-free survival (PFS), relapse and non-relapse mortality (NRM). Results: 440 pts had ECF (auto = 240, MSD = 105, MUD = 95) (Table 1). The 5 yr adjusted probabilities (AjP) of NRM were significantly lower with autoHCT (5%), versus MSD (17%) or MUD (33%) HCT (p<0.0001). 5 yr AjP of relapse were significantly lower with MSD (31%) or MUD HCT (23%), versus autoHCT (58%; p<0.0001). AjP of 5 yr PFS following auto, MSD and MUD HCT were 38%, 52% and 43% (p=.006) respectively. The AjP of 5 yr OS was significantly higher following autoHCT (70%) or MSD HCT (73%) versus MUD HCT (49%; p=0.004). Conclusions: AutoHCT for FL pts with ECF has low NRM and 5 yr OS rates (70%) that are provocatively higher than historical data (~50%). MSD HCT had the lowest relapse rate with similar survival. A prospective trial confirming the role of HCT in ECF FL is warranted. [Table: see text]