A comparison of long-term outcomes of donor lymphocyte infusions and tyrosine kinase inhibitors in patients with relapsed CML after allogeneic hematopoietic cell transplantation

Background Donor lymphocyte infusion (DLI) and tyrosine kinase inhibitors (TKIs) are the 2 standard treatment options in chronic myeloid leukemia (CML) that relapses after hematopoietic cell transplantation (HCT), but reports comparing long-term outcomes of these modalities are rare. Patients and Methods A total of 46 patients were treated with either DLI (n = 28) or TKIs (n = 18) during a first relapse of CML after HCT between 1993 and 2012. The stage of relapse was the chronic phase in 37 patients and the advanced phase in 9 patients. All patients had myeloablative conditioning without T-cell depletion during HCT. The median interval between HCT and treatment for relapse was 34 (range, 2-197) months. Results At a median follow-up of 146 and 70 months, respectively, 32% of the DLI group and 33% of the TKI group had died. Six (21%) patients initially treated with DLI received TKIs during a second relapse. In multivariable analyses, DLI was associated with inferior overall survival (OS) (hazard ratio [HR], 37.4; 95% confidence interval [CI], 2.2-625.4; P =.01), shorter failure-free survival (FFS) (HR, 21.15; 95% CI, 1.8-251; P =.02), higher cumulative incidence of failure (CIF) (HR, 19.5; 95% CI, 1.6-236.5; P =.02), and increased incidence of treatment-induced graft vs. host disease (GVHD) (68% vs. 6%; P =.001). Conclusion TKIs appear better than DLI in chronic-phase relapses after myeloablative non-T-cell-depleted HCT. Outcomes were poor in advanced-phase relapses irrespective of treatment modality