Image-Based Collection To Allow Isolation And Analysis Of Pure Intact Tumor Cell Populations From Ffpe: Implications For More Precise Her2 Fish Analysis.

e12094Background: Guidelines worldwide focus on the importance of precise and accurate Fluorescent In Situ Hybridization (FISH) methods for testing companion diagnostic markers, including Human Epidermal Growth Factor Receptor 2 (HER2) gene amplification in breast cancer. Despite these guidelines, variations in test results are observed due to pre-analytical sampling. In this study, we demonstrate a unique approach to isolating pure and intact tumor cells from breast cancer Formalin-Fixed, Paraffin-Embedded (FFPE) samples for precise FISH analysis. Methods: Fifty-micron thick FFPE curls from both HER2 non-amplified breast cancer tumors (n = 4; each with a reported HER2/CEP17 ratio 1.8) and positive control SKBr3 breast cancer cells were tested. Isolation of ∼250 pure and intact cytokeratin-positive/vimentin-negative/DAPI positive cells from each sample were captured using the DEPArray platform, an automated system enabling image-based cell sorting with single-cell resolution for pure cell population isola...