Acute leukemia of dendritic cell lineage in childhood: incidence, biological characteristics and outcome

CD4+ CD56+ malignancies have only recently been related to dendritic cell (DC) lineage. The few cases described, mostly adults and elderly, typically present with cutaneous lesions, followed by disseminated tumor localizations within a few months, with a generally very aggressive course and fatal outcome, despite the different therapeutic approaches employing chemotherapy and/or radiotherapy. Considering that leukemias in childhood and in adults are different diseases, we describe three pediatric cases to help compare the biological characteristics, immunophenotype, clinical features, treatment response and incidence of this disease in both age groups. From a total 1363 new patients with acute leukemia (AL), we report three cases with blasts of French – American – British L2 morphology, an absence of the most specific markers for myeloid, T or B lineage and lacking CD34, which led us to evaluate the blasts with an extensive panel of antibodies, including those related to the other putative pathways of lym...