Altered neutrophil immunophenotypes in childhood B‑cell precursor acute lymphoblastic leukemia

An increasing number of evidences suggest a genetic predisposition in acute lymphoblastic leukemia (ALL) that might favor the occurrence of the driver genetic alterations. Such genetic background might also translate into phenotypic alterations of residual hematopoietic cells. Whether such phenotypic alterations are present in bone marrow (BM) cells from childhood B-cell precursor (BCP)-ALL remains to be investigated. Here we analyzed the immunophenotypic profile of BM and peripheral blood (PB) maturing/matured neutrophils from 118 children with BCP-ALL and their relationship with the features of the disease. Our results showed altered neutrophil phenotypes in most (77%) BCP-ALL cases. The most frequently altered marker was CD10 (53%), followed by CD33 (34%), CD13 (15%), CD15/CD65 (10%) and CD123 (7%). Of note, patients with altered neutrophil phenotypes had younger age (p = 0.03) and lower percentages of BM maturing neutrophils (p = 0.004) together with greater BM lymphocyte (p = 0.04), and mature B-cell (p = 0.03) counts. No significant association was found between an altered neutrophil phenotype and other disease features. These findings point out the potential existence of an altered residual hematopoiesis in most childhood BCP-ALL cases.