EVALUATION OF THE USE OF CTDNA TO DETECT IMMUNOGLOBULIN REARRANGEMENTS IN PEDIATRIC LYMPHOMAS

• Grant number: 23/05013-5
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: July 01, 2023
• End date: October 04, 2023
• Field of knowledge: Biological Sciences - Genetics - Human and Medical Genetics
• Principal Investigator: Patricia Yoshioka Jotta
• Grantee: Milena Rodrigues Marusco
• Host Institution: Centro Infantil de Investigações Hematológicas Dr Domingos A Boldrini (CIB). Campinas , SP, Brazil

Abstract

Liquid biopsy consists in the detection of any tumor material in body fluids thus, ctDNA analysis allows a non-invasive and real-time view of tumor dynamics, which can provide important information for choosing and directing therapies in patients with neoplasms. Lymphoma is a neoplasm of the lymphatic system with several subtypes divided according to their origin and molecular characteristics. Similar to acute lymphoblastic leukemia (ALL), lymphomas have clonal or oligoclonal origins, as evidenced by rearrangements of immunoglobulin (Ig) and T-cell receptor (TCR) genes. However, unlike ALI, whose diagnosis is made by bone marrow evaluation, the diagnosis of lymphoma requires biopsy of the tumor tissue, an invasive procedure that causes discomfort to patients. In this context, the present study aims to standardize the use of next-generation sequencing (NGS) for the identification of Ig and TCR rearrangements in circulating tumor DNA (ctDNA) as a tool to aid in the diagnosis and monitoring of pediatric lymphomas. A pilot study developed during the internship, was analyzed by sequencing (by NGS) of tissue samples from 23 lymphomas. Rearrangements were identified in 14 patients (60.87%). The most frequent rearrangements were IgL, IgK and IgH (26.2%), followed by TCRG (9.5%) and TCRD (11.9%).