Abstract Library

#4505 NET-IMPRESS: A novel methylation-based assay to diagnose and monitor NET patients using liquid biopsies

Introduction: Previously, we showed that analysing copy number alterations (CNAs) in cell-free DNA (cfDNA) of NET patients using shallow whole genome sequencing (sWGS) is a potential biomarker for diagnosis and follow-up (PMID: 34759042). We now present NET-IMPRESS, an easy, cost-effective methylation-based assay for detecting circulating tumour DNA (ctDNA) in NET samples.

Conference:

Presenting Author:

Authors: Mariën L, Ibrahim J, de Meulenaere N, Chhajlani S, Neefs I,

Keywords: neuroendocrine tumour, liquid biopsy, DNA methylation, copy number alterations, biomarker selection, IMPRESS technology,

#4380 Cell-free DNA concentration correlates with copy number variant (CNV)-count, describes tumour progression and nuclear instability in GEP-NETs

Introduction: Cell-free DNA (cfDNA) levels depend on various factors related to the shedding of cells and might provide valuable information on tumour state and treatment success. In a genomic profiling pilot study conducted as part of the COMPOSE Phase III multicentre open-labelled clinical trial we assessed multiple factors and their impact on cfDNA levels in 14 GEP-NET patients.

Conference:

Presenting Author: Srirajaskanthan R

Authors: Srirajaskanthan R, Capdevila J, Smutna V, Weckwerth W, Erdoe M,

Keywords: CNV, cfDNA, liquid biopsy, quantitative marker, cfDNA concentration, longitudinal, GEP-NET, genomic profiling,

#4189 Pit and pitfalls of tumor mutational burden assessment in well-differentiated pancreatic neuroendocrine tumors: Two case reports from University of Verona

Introduction: The hypermutated phenotype is used as a predictive parameter for immune-checkpoint inhibitors (ICI). However, the relationship between high TMB, the underlying mutational drivers and response to ICI is still unclear.

Conference:

Presenting Author: Trevisani E

Authors: Torresan I, Reni A, Trevisani E, Borghesani M, Rossi A,

Keywords: Neuroendocrine tumor, NGS, Tumor Mutational Burden, Alkylating agent, DNA Damage Repair, Liquid biopsy,

#4182 DNA damage repair genes alterations in pancreatic neuroendocrine tumor treated with Temozolomide

Introduction: Temozolomide (TMZ), a standard therapy for pancreatic neuroendocrine tumors (pNETs), is an alkylating agent causing missense mutations and triggering cell death.

Conference:

Presenting Author: Trevisani E

Authors: Trevisani E, Reni A, Torresan I, Borghesani M, Rossi A,

Keywords: DNA Damage Repair, Tumor mutational burden, Neuroendocrine, Temozolomide,

#4174 Uncovering the genomic profiling of metastatic pheochromocytomas and paragangliomas: Leveraging plasma circulating tumor DNA for comprehensive genetic characterisation and monitoring

Introduction: Liquid biopsy, notably plasma circulating tumor DNA (ctDNA), is a non-invasive approach to elucidate the tumoral genomic profile from a blood sample. Pheochromocytomas and paragangliomas (PPGL) are often operated, characterized by quiet genomes and usually indolent tumor growth. However, challenges arise with metastatic tumors due to accessibility, catecholamine-related crises and surgery issues. Thus, molecular mechanisms transitioning from indolent to metastatic tumors are largely unexplored.

Conference:

Presenting Author:

Authors: Arenillas Lallana C, Moreno-Cárdenas A, Casteràs A, García-Álvarez A, Hernando J,

Keywords: liquid biopsy, ctDNA, metastasis, pheochromocytoma, paraganglioma, genomic targets,