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Regentova Olga

Russian Scientific Center of Roentgenoradiology, Russia

Title: Plasma concentrations of the mutant BRAF gene in children with HGG and DIPG during radiotherapy as a marker of prognosis

Abstract

Introduction: The search for genetic markers of prognosis seems promising for individualization of treatment programs for patients with brain tumors. Purpose. To study the dynamics of the concentration of mutant DNA forms gene BRAF in peripheral blood plasma during and after radiation therapy and compare these data with the effect of treatment. Materials and methods. Digital droplet PCR (ddPCR) was used to determine the concentration of mutant tumor DNA in 209 blood plasma samples (groups included 57 patients with pons tumors and 29 patients with glioma of the other localization). The samples were obtained before the course of RT, during RT (5-8 fraction) and after RT(27-30 fraction). According to the results of radiation therapy, patients were divided into two groups: 1 – the onset of tumor recurrence less than 6 months after the end of the course of RT; 2 – stabilization of the process for 6 months or more after the end of the course of RT. Results. A significant increase in the relative concentration of mutant (V600E) DNA of the BRAF gene in peripheral blood at the beginning of the RT course and its decrease by the end of the course in the relapse-free group was shown. No changes or an increase in BRAFV600E levels by the end of the RT course was typical for patients with relapse in the early stages. Summary. Methods of liquid biopsy allow to estimate changes in the amount of mutant (tumor) DNA in peripheral blood plasma in children with brain glioma in RT. Increase in the level of mutant DNA correlates with a more stable effect of the treatment.

Biography

Olga Regentova is Candidate of Science in Medicine at the age of 35. The theme of science work is “Re-irradiation DIPG in children”. She is the head of the department of radiotherapy for children of Russian Scientific Center of Roentgenoradiology. She has more than 25 publications.