HLA class II EM in the GVH direction, stratified by the median, and relapse: subgroup analyses. (A-B) Greater class II EM in the GVH direction was associated with reduced incidence of relapse in AML patients but not in non-AML patients, and this association remained significant after multivariate analysis. (C-D) Greater class II EM in the GVH direction was associated with reduced incidence of relapse in AML patients with active disease, but this association did not remain significant after multivariate analysis.