Analysis of HER2 status in breast carcinoma by fully automated HER2 fluorescence in situ hybridization (FISH): comparison of two immunohistochemical tests and manual FISH. Issue 9 (20th December 2013)

• Record Type: Journal Article
• Authors: Yoon, Nara; Do, In‐Gu; Cho, Eun Yoon
• Is Part Of: Apmis. Volume 122:Issue 9(2014:Sep.)
• Page Start: 755
• Page End: 760
• Publication Date: 2013-12-20
• Subjects: Pathology -- Periodicals; Microbiology -- Periodicals; Immunology -- Periodicals; 572
• DOI: 10.1111/apm.12215
• Languages: English
• ISSNs: 0903-4641

Abstract

<abstract abstract-type="main" id="apm12215-abs-0001"> <title> <x xml:space="preserve">Abstract</x> </title> <p>Easy and accurate HER2 testing is essential when considering the prognostic and predictive significance of HER2 in breast cancer. The use of a fully automated, quantitative FISH assay would be helpful to detect <italic>HER2</italic> amplification in breast cancer tissue specimens with reduced inter‐laboratory variability. We compared the concordance of <italic>HER2</italic> status as assessed by an automated FISH staining system to manual FISH testing. Using 60 formalin‐fixed paraffin‐embedded breast carcinoma specimens, we assessed HER2 immunoexpression with two antibodies (DAKO HercepTest and CB11). In addition, <italic>HER2</italic> status was evaluated with automated FISH using the Leica FISH System for BOND and a manual FISH using the Abbott PathVysion DNA Probe Kit. All but one specimen were successfully stained using both FISH methods. When the data were divided into two groups according to <italic>HER2</italic>/CEP17 ratio, positive and negative, the results from both the automated and manual FISH techniques were identical for all 59 evaluable specimens. The <italic>HER2</italic> and CEP17 copy numbers and <italic>HER2</italic>/CEP17 ratio showed great agreement between both FISH methods. The automated FISH technique was interpretable with signal intensity similar to those of the manual FISH technique. In contrast with manual FISH, the automated FISH technique showed well‐preserved architecture due to low membrane digestion. HER2 immunohistochemistry and FISH results showed substantial significant agreement (κ = 1.0, p < 0.001). <italic>HER2</italic> status can be reliably determined using a fully automated <italic>HER2 </italic>FISH system with high concordance to the well‐established manual FISH method. Because of stable signal intensity and high staining quality, the automated FISH technique may be more appropriate than manual FISH for routine applications.</p> </abstract>