Childhood myeloid neoplasms with PTPN11 mutations in Brazil

Abstract The diagnostic variables to distinguish myeloproliferative disorders (MPD) and acute myeloid leukemia (AML) is still a challenge in developing countries. We aimed to explore the prevalence of RAS pathways mutations with a focus on PTPN11 mutation in MPD and AML affecting pediatric patients. RAS and PTPN11 mutations were found in 10.4% and 3.3% of AML cases, respectively, more common in males (p=0.021) and myelomonocytic subtypes (p=0.001). In juvenile myelomonocytic leukemia (JMML), RAS mutations were found in 16.6% while PTPN11 mutations 28.8% of the cases. PTPN11 mutations conferred a poor prognosis compared to wild type patients (48 months-OS 12.5±10.8% and 33.2±4.0, respectively), associated with poor outcome in childhood AML. In conclusion, PTPN11 status should be identified in the diagnosis of MN as a predictive marker of outcome in childhood AML.