Professional paper

Interlaboratory concordance in HER-2 positive breast cancer

Nives Jonjić orcid.org/0000-0003-2995-0766 ; Department of Pathology, School of Medicine, University of Rijeka, Rijeka, Croatia
Elvira Mustać ; Department of Pathology, School of Medicine, University of Rijeka, Rijeka, Croatia
Snježana Tomić ; Clinical Department of Pathology, Split University Hospital Center, Split, Croatia
Jasminka Jakić Razumović ; Clinical Department of Pathology, Zagreb University Hospital Center, Zagreb, Croatia
Božena Šarčević ; Clinical Department of Pathology, Sestre milosrdnice University Hospital Center, Zagreb, Croatia
Valerija Blažičević ; Clinical Department of Pathology, Osijek University Hospital Center, Osijek, Croatia
Loredana Peteh Labinac ; Department of Pathology, Pula General Hospital, Pula, Croatia
Dražen Švagelj orcid.org/0000-0003-2574-675X ; Department of Pathology, Vinkovci General Regional Hospital, Vinkovci, Croatia
Andrina Kopjar ; Department of Pathology, Varaždin General Hospital, Varaždin, Croatia
Nataša Lisica Šikić ; Department of Pathology, Zadar General Hospital, Zadar, Croatia
Branka Vrbičić ; Department of Pathology, Šibenik-Knin General Hospital, Šibenik, Croatia
Igor Borić ; Department of Pathology, Dubrovnik General Hospital, Dubrovnik, Croatia

Abstract

Accurate assessment of HER -2 status is essential for identifying patients who will benefit from HER -2 targeted therapy. The aim of the present study was to show results on the concordance between local and central laboratory testing results in HER -2 positive breast cancer patients. In cases with discordant findings, the immunohistochemical (IHC) and/or in situ hybridization (FISH/SISH) analysis was performed in central laboratories. A total of 104 out of 143 (72.72%) breast carcinoma cases were HER -2 positive (score 3+), while nearly 14% of tumors (20/43) showed weak (score 2+) and 12% (19/143) negative IHC staining (score 0 and 1+). After repeated IHC and ISH, 88% (126/143) were classified as HER -2 positive and 12% (17/143) as HER -2 negative cases. The results obtained are in agreement with many studies that confirmed similar discordance in HER -2 testing by IHC and/or FISH between local and central laboratory. Thus, our findings as well as those from other studies support the importance of regular quality assessment of the staining procedures performed and consistency of interpretation of HER -2 test results.

Keywords

Breast cancer; HER-2; Immunohistochemistry; In situ hybridization, fluorescence; Quality

Hrčak ID:

155443

URI

https://hrcak.srce.hr/155443

Publication date:

1.12.2015.

Article data in other languages: croatian

Visits: 1.844 *