Treatment of relapsed leukemia after unrelated donor marrow transplantation with unrelated donor leukocyte infusions

The efficacy and toxicity of donor leukocyte infusions (DLI) after unrelate d donor bone marrow transplantation (BMT) is largely unknown. We identified 58 recipients of unrelated DLI (UDLI) for the treatment of relapsed diseas e from the National Marrow Donor Program database. A retrospective analysis was performed to determine response, toxicity, and survival after UDLI and to identify factors associated with successful therapy. UDLI was administe red for relapsed chronic myelogenous leukemia (CML) (n = 25), acute myeloge nous leukemia (AML) (n = 23), acute lymphoblastic leukemia (ALL) (n = I), a nd other diseases (n = 3). Eight patients were in complete remission (CR) b efore UDLI, and 50 were evaluable for response. Forty-two percent (95% conf idence interval [CI], 28%-56%) achieved CR, including 11 of 24 (46%; 95% CI , 26%-66%) with CML, 8 of 19(42%; 95% CI, 20%-64%) with AML, and 2 of 4 (50 %; 95% CI, 1%-99%) with ALL. The estimated probability of disease-free surv ival (DFS) at 1 year after CR was 65% (95% CI, 50%-79%) for CML, 23% (95% C I, 9%-38%) for AML, and 30% (95% CI, 6%-54%) for ALL. Acute graft-versus-ho st disease (GVHD) complicated UDLI in 37% of patients (grade II-IV, 25%). A total of 13 of 32 evaluable patients (41%) developed chronic GVHD. There w as no association between cell dose administered and either response or tox icity. In a multivariable analysis, only a longer interval from BMT to rela pse and BMT to UDLI was associated with improved survival and DFS, respecti vely. UDLI is an acceptable alternative to other treatment options for rela pse after unrelated donor BMT. (Blood. 2000;95:1214-1221) (C) 2000 by The A merican Society of Hematology.