Description of Molecular Prognostic Markers in AML Uruguayan Patients

Acute myeloblastic leukemias (AML) are the most frequent acute leukemias in adults. Recent genomic and candidate gene studies identified novel recurrent somatic mutations in patients with AML with biological, clinical and therapeutic significance. In Uruguay, the characterization of AML is dependent on the integration of cytomorphology, immunophenotype, cytogenetics and molecular biology (mutations in FLT3, NPM1, CEBPA and cKIT). This allows stratification in prognostic risk groups and rationalization of therapeutic resources. However, with this molecular markers, complete stratification is not always succesful in patients with normal karyotype ( NK) .

In order to expand the AML genetic markers analysis in Uruguayan patients ( 3.000.0000 persons country ) ; DNA samples from 49 adult patients at the onset of the disease and 3 healthy controls were analyzed by next generation sequencing (NGS, Illumina) using a customized panel of 30 cancer associated genes. After excluding synonymous variants and those with a population frequency >1%, we ended with 493 variants in promoters and intron ends, and 173 in the 28 genes coding regions. Notably, all patients had at least one variant.

While none of the non-coding region variants were reported as pathogenic in COSMIC and/or ClinVar databases, 45 of those falling in coding regions were reported as pathogenic. The pathogenic variants were detected in 36/49 patients and 1 healthy control distributed in 16 genes. The most affected genes were TET2, NRAS, DNMT3, FLT3 and cKIT with 7, 6, 5, 4, 4 variants respectively.

This preliminar findings in this study, highlight the relevance of detecting gene variability underlying prognostic risk subgroups to deliver patient tailored clinical decision support. The correlation between the genetic abnormalities, associated with the clinicopahtological features and the epigenetic studies have prognostic significance, and are continued to be analyzed.