CD33 and precursor B-cell acute lymphoblastic leukemia: In our analysis, the CD13/CD33+ and CD13/CD33− groups showed comparable incidences of CR1, CNS involvement, relapse and death, as well as time to CNS involvement, RFS and OS, suggesting that CD13/CD33 has no adverse effect on the clinical course, prognosis, and outcome of patients with B‐ALL.