Reference Size Matching, Whole-Genome Amplification, and Fluorescent Labeling as a Method for Chromosomal Microarray Analysis of Clinically Actionable Copy Number Alterations in Formalin-Fixed, Paraffin-Embedded Tumor Tissue

Publication date: May 2018Source: The Journal of Molecular Diagnostics, Volume 20, Issue 3Author(s): Shelly R. Gunn, Shailin Govender, Cynthe L. Sims, Aditi Khurana, Samuel Koo, Jayne Scoggin, Mathew W. Moore, Philip D. CotterCancer genome copy number alterations (CNAs) assist clinicians in selecting targeted therapeutics. Solid tumor CNAs are most commonly evaluated in formalin-fixed, paraffin-embedded (FFPE) tissue by fluorescence in situ hybridization. Although fluorescence in situ hybridization is a sensitive and specific assay for interrogating preselected genomic regions, it provides no information about coexisting clinically significant copy number changes. Chromosomal microarray analysis is an alternative DNA-based method for interrogating genome-wide CNAs in solid tumors. However, DNA extracted from FFPE tumor tissue produces an essential, yet problematic, sample type. The College of American Pathologists/American Society of Clinical Oncology guidelines for optimal tumor tissue handling, published in 2007 for breast cancer and in 2016 for gastroesophageal adenocarcinomas, are lacking for other solid tumors. Thus, cold ischemia times are seldom monitored in non–breast cancer and non–gastroesophageal adenocarcinomas, and all tumor biospecimens are affected by chemical fixation. Although intended to preserve specimens for long-term storage, formalin fixation causes loss of genetic information through DNA damage. Herein, we describe a reference size matching, whole-g...
Source: The Journal of Molecular Diagnostics - Category: Pathology Source Type: research