Chronic Myeloid Leukemia in Children and Adolescents (A bout 2 cases)

Abstract

Pediatric chronic myelogenous leukemia is a rare entity (2 to 5% of childhood leukemia) classified as myeloproliferative neoplasia characterized by the presence of the BCR-ABL fusion gene, the oncogenic product of the translocation (9; 22), responsible for the disease by its deregulated tyrosine kinase activity. Pediatric chronic myelogenous leukemia evolves spontaneously in three phases: chronic, accelerated and blast, during which the malignant clone gradually loses its capacity for differentiation. The diagnosis is based on the clinic mainly by the presence of a marked splenomegaly, the blood count by a hyperleukocytosis generally greater than 250,000 / mm³, myelogram which shows granular hyperplasia associated with no blast infiltration and morphologically define the stage of the disease, cytogenetics and molecular biology which confirms the diagnosis by the detection of the Philadelphia chromosome and more specifically the molecular abnormality BCR-ABL1. Imatinib is the treatment of choice for curative purposes used in our hospital structure, but regular monitoring of residual molecular disease and the absence of cytogenetic evolution are essential to understand resistance to TKIs (the inhibitor of tyrosine activity kinase) and detect disease progression. We report two observations of pediatric chronic myeloid leukemia, describing the different diagnostic aspects and which were in agreement with clinical and biological data in the literature.