Philadelphia Chromosome Positive Childhood

In a 3-yr period, the Philadelphia chromosome (Ph’) was found in 4 of 43 children with acute lymphoblastic leukemia (ALL) in whom chromosomes were studied at diagnosis. The clinical, morphological, cytochemical, and immunologic findings in the Ph’-positive (Ph’ + ) cases were consistent with typical childhood ALL, indicating that identification of cases requires chromosome studies. A review of all reported cases of Ph’ + childhood ALL shows that Ph’ + patients are older and have higher initial platelet and white blood cell counts (WBC) than most children with ALL. However, a life table comparison between the reported cases of Ph’ + ALL in children and randomly selected age-, sex-, and WBC-matched controls with ALL shows the duration of first marrow remission to be significantly shorter (p < 0.02) for the Ph’ + cases. Ph’ + ALL is a distinct subtype of childhood ALL that is not rare and can be identified only by cytogenetic studies. The prognosis is poor. Cytogenetic studies should be done prospectively in a large group of children with ALL to define further this subgroup of patients and to confirm the findings of this retrospective analysis.