Distribution of ABO blood groups in childhood acute leukemia.

The distribution of ABO blood groups was determined in a multicenter study of 682 pediatric patients with acute lymphoblastic leukemia (ALL) and 224 patients with acute myeloid leukemia (AML) up to 12 years old. The overall distribution of blood groups was significantly different in both ALL and AML groups from the control group (p < .001). In the ALL group there were 56.5% (95% CI: 45.8-67.1) more patients with O blood group, 35.8% (95% CI: 27.0-44.5) fewer patients with A blood group, and 26.9% (95% CI: 12.7-39.2) fewer patients with B blood group. In the AML group, there were 28.8% (95% CI: 10.8-46.9) more patients with A blood group. The results indicate that alteration in ABO antigens might be associated with an increased risk of ALL.