CHEMOTHERAPY VERSUS TRANSPLANTS FOR ACUTE MYELOGENOUS LEUKEMIA IN 2NDREMISSION

The best therapy for persons with acute myelogenous leukemia (AML) in 2nd remission is unknown. Bone marrow transplants from an HLA-identica l sibling are reported to be better than chemotherapy but this is cont roversial. The objective of the study was to compare 3-year leukemia-f ree survival (LFS) in comparable subjects receiving chemotherapy or a transplant. 485 persons with AML in 2nd remission were studied. The ch emotherapy cohort included 244 persons treated on trials of the Britis h Medical Research Council, Eastern Cooperative Oncology Group and MD Anderson Hospital. The transplant cohort included 257 persons transpla nted worldwide and reported to the International Bone Marrow Transplan t Registry (16 were also chemotherapy subjects). Subjects were selecte d for comparable age and year of treatment. Preliminary analyses ident ified two factors correlated with LFS: age less than or equal to or > 30 years and Ist remission duration less than or equal to or > 1 year; subsequent analyses were partitioned accordingly. Three-year probabil ities of treatment-related mortality with chemotherapy and transplants were 7% (95% confidence interval, 3-15%) vs 56% (49-63%). Three-year leukemia relapse probabilities were 81% (74-86%) vs 41% (33-49%), Thre e-year probabilities of LFS were 17% (12-23%) vs 26 (20-32%). Cohort a nalysis showed significantly higher LFS with transplants vs chemothera py in persons less than or equal to 30 years and Ist remissions > 1 ye ar (41% (29-53%) vs 17% (7-32%); P = 0.017) and those in > 30 years wi th Ist remissions less than or equal to 1 year (18% (9-29%) vs 7% (2-1 6%); P = 0.046). Others had comparable LFS with both treatments. These data indicate better LFS with HLA-identical sibling transplants than chemotherapy in some persons with AML in 2nd remission.