A second common phenotype in our study was CD10+/CD34–, consistent with another study.9 B-cell acute lymphocytic leukaemia with the t(1;19) translocation often has this phenotype, and reportedly with a favourable prognosis with intensive chemotherapy regimens.28 The prevalence of t(1;19) has been observed to be around 5% e,28 much lower than the associated phenotype that we report here. This evidence concerns the gene CD34 and precursor B-cell acute lymphoblastic leukemia.