# Application of the FISH method and high-density SNP arrays to assess genetic changes in neuroblastoma—research by one institute

## TL;DR

This study uses FISH and SNP arrays to detect genetic changes in neuroblastoma, helping identify high-risk patients and improve treatment decisions.

## Contribution

The study demonstrates the effectiveness of FISH and high-density SNP arrays in detecting MYCN amplification and structural changes in neuroblastoma.

## Key findings

- FISH detected MYCN amplification in 22.4% of patients using paraffin-embedded tissues and intraoperative imprints.
- High-density SNP arrays are highly accurate for detecting structural changes in neuroblastoma tumors.
- Genetic changes, including MYCN amplification, significantly influence neuroblastoma clinical behavior.

## Abstract

Neuroblastoma is the most common extracranial solid tumor in children. Amplification of the MYCN gene has been observed in approximately 20%–30% of tumors. It is strongly correlated with advanced-stage disease, rapid tumor progression, resistance to chemotherapy and poor outcomes independent of patient age and stage of advanced disease. MYCN amplification identifies high-risk patients. To assess neuroblastoma tumors with MYCN amplification we used paraffin-embedded tissue sections in 57 patients and intraoperative tumor imprints in 10 patients by fluorescence in situ hybridization (FISH). Positive results for MYCN amplification have been observed in twelve patients’ paraffin-embedded tissue sections and in three patients’ intraoperative tumor imprints, which represents 22.4% of all patients tested in the analysis. Fluorescence in situ hybridization is a highly sensitive and useful technique for detecting MYCN amplification on paraffin-embedded tissue sections of neuroblastoma tumors and intraoperative tumor imprints thus facilitating therapeutic decisions based on the presence or absence of this important biologic marker. The presence of structural changes, regardless of MYCN gene amplification status, influences the clinical behavior of neuroblastoma. High-Density SNP Arrays have emerged as the perfect tools for detecting these changes due to their exceptional accuracy, sensitivity and ability to analyze copy number and allele information. Consequently, they are proven to be highly valuable in the genomic diagnosis of immature neuroectodermal tumors.