Managing post allograft relapse of myeloid neoplasms: azacitidine and donor lymphocyte infusions as salvage therapy.

Azacitidine (Aza) may promote cytotoxic effects against hematologic tumor cells when combined with donor lymphocyte infusions (DLIs). This study sought to verify Aza-DLI's efficacy and tolerability in patients with relapsed acute myeloid leukemia (AML) or myelodysplastic syndrome (MDS) following allogeneic stem cell transplantation (SCT) and identify cohorts benefitting most from therapy. Twenty-eight patients with recurrent AML or MDS following SCT received Aza-DLI. One-year overall survival (OS) after therapy initiation was 44%; two-year OS was 35%. Molecular/cytogenetic-only relapse, the development of cGVHD after therapy initiation, and a greater number of Aza and DLI were associated with remission. There was a trend toward higher absolute CD4+ cell count in those achieving remission. This study demonstrates Aza-DLI to be effective and highlights the importance of minimal residual disease testing and alloreactivity in managing post allograft relapsed hematological malignancy.