The human epidermal growth factor receptor 2 screening tests for breast cancer suggested by the new updated recommendation of the american society of clinical oncology/college of american pathologists will involve a rise of the in-situ hybridization tests for the European laboratories of pathology.

Christian Garbar,Aude-Marie Savoye,Eva Brabencova,Corinne Mascaux,Hervé Curé

doi:10.1155/2014/793695

Christian Garbar, Aude-Marie Savoye + Show 3 more

Open Access

https://doi.org/10.1155/2014/793695

Copy DOI

Journal: ISRN Oncology	Publication Date: Apr 22, 2014
Citations: 33	License type: CC BY 3.0

Affiliation: Institut Jean Godinot

Abstract

Aims. The differences between the 2007 and the 2013 ASCO/CAP HER2 guidelines have been compared. We also discussed the potential consequences in our pathological practice. Material and Methodology. 189 HER2 fluorescence in situ hybridisation (FISH) tests were performed from 1016 preliminary HER2 immunohistochemical tests (IHC). All cases were reviewed and reclassed following the 2007 and 2013 ASCO/CAP recommendations. Results. The 2013 version decreased false-negative IHC (3/118 versus 1/54, P = ns) and created more 2+ IHC (40/186 versus 89/186, P = 0.001) or more 3+ IHC (9/186 versus 39/186, P = 0.001). One false-positive IHC was described for the 2013 version (0/9 versus 1/39, P = ns). Equivocal FISH was reduced (8/186 versus 2/186, P = ns). An estimation based on our data for 1000 patients showed a rise of our FISH tests for the control of 2+ IHC (180 tests for the 2007 version versus 274 tests for the 2013 version or FISH work overflow is +52%) and for the control of 2+/3+ IHC (300 for the 2007 version versus 475 for the 2013 version or FISH work overflow is +58%). Conclusions. The new 2013 ASCO/CAP guidelines have detected more HER2 positive cases but have increased the number of FISH tests.

Highlights

In Europe, the breast cancer incidence is 464.000 cases representing the most common cause in women [1]
Equivocal immunohistochemical tests (IHC) (2+) was human epidermal growth factor receptor 2 (HER2) gene amplified on fluorescence in situ hybridisation (FISH) in 52.5% (21/40)
The FISH work overflow for the 2013 version was, respectively, +52% for the controls of 2+ IHC and +58% for the controls of 2+ and 3+ IHC. This retrospective study, based on selected revised IHC and FISH cases, has demonstrated that the 2013 American Society of Clinical Oncology (ASCO)/College of American Pathologists (CAP) guidelines of HER2 evaluation are better than the 2007 recommendations

Summary

Introduction

In Europe, the breast cancer incidence is 464.000 cases representing the most common cause in women [1]. One of disadvantages of this 2007 version was the true possibility to make false-negative IHC tests and nonnegligible number of equivocal FISH. To answer to this reality, an important update of the ASCO/CAP HER2 recommendations has been recently published to improve the accuracy of the HER2 test [6]. The aim of this retrospective work is to compare the main differences between the 2007 and the 2013 ASCO/CAP HER2 guidelines and the potential consequences in our routine practice

Materials and Methodology

Results

E N P Total E N P Total

Discussion