Among 43 cases with CD34+ leukemia (CD34+, ≥20% leukemia cells were CD34+) 34 expressed Fas in ≥20% of cells and 19 expressed Fas in ≥50% cells. Among 21 CD34− (CD34−) cases, 19 and 14 expressed Fas in ≥20% and 50% of leukemia cells, respectively. Range and median are shown.