T-cell receptor τδ+/CD3+4-8- T-cell acute lymphoblastic leukemias: A distinct subgroup of leukemias in children. A report of five cases

Abstract

In a 10-year study of T-cell acute lymphoblastic leukemias (T-ALL) in children, we have identified five cases expressing the T-cell receptor τδ(TCRτδ). The incidence (26%) of TCRτδ+ T-cell leukemias in our material was high. Clinically, the TCRτδ+ leukemias represented a distinct subgroup of T-cell leukemias. Mean age at onset of disease, 1.8 years, was remarkably low for mature T-cell leukemias. White blood cell counts were high, lymph node enlargements were discrete, and no mediastinal tumors were seen. Four of five TCRτδ+ leukemias carried rearrangements of the Cτ2 gene, and transcribed the T-early alpha genetic element. © 1991 by The American Society of Hematology.