G-CSF-MOBILIZED DONOR LEUKOCYTE INFUSIONS AS IMMUNOTHERAPY IN ACUTE-LEUKEMIA RELAPSING AFTER ALLOGENEIC MARROW TRANSPLANTATION

Eight patients who relapsed with acute leukemia within a year after al logeneic BMT were treated with G-CSF-mobilized donor leukocyte infusio ns (mDLI) to induce GVHD as a form of immunotherapy. Prior to mDLI, 7 who had systemic relapse received one (2 AML, 1 ALL, 1 CML myeloid bla st crisis) or two (2 AML, 1 ALL) rounds of conventional dose induction chemotherapy, and 1 patient with isolated central nervous system (CNS ) lymphoid blast crisis CML received intrathecal chemotherapy followed by craniospinal irradiation. G-CSF (10 mu g/kg/day) was given to orig inal HLA-matched sibling donors for 4-5 days before leukapheresis of a t least 6.0 x 10(8) mononuclear cells per kilogram of recipient weight , No GVHD prophylaxis was used when mDLI was given in 6 patients at th e nadir of hematologic counts and in 2 who were in hematologic remissi on, There was no regimen-related mortality, as pancytopenic patients h ad rapid recovery of neutrophil counts (6-18 days after mDLI), All pat ients developed moderate to severe GVHD (5 grade III/IV, 3 grade II) a t a median of 30 days (range 22-59) after mDLI, Two patients Pied of c omplications from refractory GVHD while in remission. The other 6 had short remissions lasting 2.2-9.4 months until leukemic relapse as thei r GVHD was reversed by corticosteroids with or without cyclosporine. P atients who relapse with acute leukemia within a year after BMT still have a poor prognosis. The success of GVHD as a form of immunotherapy in these patients may depend on the ability to control it to a state t hat is both safe and continually exerting an antileukemia effect.