A sub-type of acute lymphoblastic leukemia affecting cells early in the B lymphocyte lineage. This type accounts for about 80 percent of all cases of childhood acute lymphoblastic leukemia.
The majority of patients (77%) was diagnosed with common-ALL (n = 47); there were also 10 patients with pre-B, 1 patient with pre-pre-B ALL, and 3 patients (4.9%) with T-ALL.