is a frequent biomarker of adverse prognosis in Mexican pediatric patients with B-acute lymphoblastic leukemia.

Background: Recurrent genetic alterations contributing to leukemogenesis have been identified in pediatric B-cell Acute Lymphoblastic Leukemia (B-ALL), and some are useful for refining classification, prognosis, and treatment selection. is a complex biomarker associated with a poor prognosis. It is characterized by deletion coexisting with , , or PAR1 region deletions. The mutational spectrum and clinical impact of these alterations have scarcely been explored in Mexican pediatric patients with B-ALL. Here, we report the frequency of the profile and the mutational spectrum of , and genes and evaluate their impact on overall survival (OS) in a group of patients with B-ALL.

Methods: A total of 206 pediatric patients with B-ALL were included. DNA was obtained from bone marrow samples at diagnosis before treatment initiation. A custom-designed next-generation sequencing panel was used for mutational analysis. Kaplan-Meier analysis was used for OS estimation.

Results: We identified the profile in 21.8% of patients, which was higher than that previously reported in other studies. A significantly older age (), a trend toward high-risk stratification (), and a decrease in 5-year Overall Survival (OS) () were observed, although heterogeneous treatment protocols in our cohort would have impacted OS. A mutation frequency higher than that reported was found for (35.9%) and (35.9%) but lower for (26.6%). group was older at diagnosis (), and most of them were classified as high-risk (73.8%, ), while patients with had a higher leukocyte count () and a tendency toward a higher percentage of blasts (98.6%, >50% blasts, ) than the non-mutated patients. A decrease in OS was found in and patients, but the significance was lost after was removed.

Discussion: Our findings demonstrated that Mexican patients with B-ALL have a higher prevalence of genetic markers associated with poor outcomes. Incorporating genomic methodologies into the diagnostic process, a significant unmet need in low- and mid-income countries, will allow a comprehensive identification of relevant alterations, improving disease classification, treatment selection, and the general outcome.