Immunotherapy following relapse of acute leukaemia after T‐cell‐replete allogeneic peripheral blood progenitor cell transplantation: importance of new onset chronic graft‐versus‐host disease

Abstract

To further define the relative impact of immunotherapy and subsequent development of graft-versus-host disease (GVHD) on survival in patients with relapsed acute leukaemia postallogeneic hematopoietic stem cell transplant (SCT), we performed a single-centre retrospective analysis of 32 actively treated patients between 2003 and 2011. A total of 13 patients were identified who were treated actively with cessation of immunosuppression ± Fludarabine, Cytarabine, G-CSF (FLAG) induction, but no donor leucocyte infusion (DLI) (non-DLI group) and 19 patients received the same step-wise therapy plus G-CSF mobilized DLI (G-DLI group). Groups were not statistically different with regards to baseline characteristics; however, the G-DLI group contained more sibling donors as opposed to unrelated donors than the non-DLI group. With a median follow-up of 47months, the median overall survival (OS) of the non-DLI and G-DLI groups was not statistically different (8months vs. 9months, respectively, P=0.5). Survival at 3years was <10% in both groups. Univariate analysis identified response to FLAG, and new onset chronic GVHD as the only factors associated with improved OS. Second donor stem cell infusions are unwarranted in the treatment of relapse after allogeneic SCT and therapeutic strategies should focus on cytoreduction followed by immune modulation with the aim of invoking chronic GVHD.