CML Pediatric ITK Response According to Molecular Identification at Diagnosis

Treatment of chronic myeloid leukemia (CML) has been revolutionized by tyrosine kinase inhibitor (TKI). Nevertheless, case of failure and suboptimal response are still observed even in children. Pediatric CML is a rare disease and differs from adult in terms of disease presentation and treatment response underlying a likely different CML biology. Molecular mechanisms that induce resistance to TKI are still poorly characterized except mutations in the tyrosine kinase domain of BCR::ABL1. We propose to search for a molecular signature to predict the response to TKI in the pediatric population.

Inclusion Criteria:Age at diagnosis less than or equal to 18 yearsPresence of a Philadelphia chromosome detected by cytogenetic analysis (conventional karyotype or Fluorescence In Situ Hybridization (FISH)) and a BCR ::ABL1 transcript e13a2 ou e14a2Diagnosis in chronic phase according to the European Leukemia Net (ELN) criteriaFirst-line treatment with TKIsPossible pre-treatment with hydroxyureaDNA available at diagnosisRNA available for a sub-group patients (8 responders vs 8 no responders)Exclusion Criteria:Age at diagnosis more than 18 yearsDiagnosis in accelerated phase or blastic phaseFirst line treatment other than TKI