High inter-observer agreement in immunohistochemical evaluation of HER-2/neu expression in breast cancer: a multicentre GEFPICS study.

Abstract

The accurate determination of HER-2 in invasive breast cancer has become a critical issue, particularly in the context of the results of recent trastuzumab (Herceptin((R))) adjuvant trials. This multicentre study evaluated inter-observer reproducibility in interpretation of HER-2 immunostains performed in different laboratories according to their in-house technique. A total of 74 HER-2 immunostains were evaluated by 16 pathologists and by a central review committee. As determined by central review, the HER-2 score was 0 in 33 cases (44%), 1+ in 10 cases (13%), 2+ in 9 cases (12%) and 3+ in 23 cases (31%). The overall kappa value was good (kappa=0.75). Agreement was excellent for the 0/1+ group (kappa=0.85) and for the 3+ group (kappa=0.82). As expected, the score 2+ group showed poor agreement (kappa=0.38). A quality assurance process showed that ring studies and adherence to national guidelines greatly improve inter-observer reproducibility.

• Authors: Magali Lacroix-Triki, Simone Mathoulin-Pelissier, Jean-Pierre Ghnassia, Gaetan Macgrogan, Anne Vincent-Salomon, Véronique Brouste, Marie-Christine Mathieu, Pascal Roger, Frédéric Bibeau, Jocelyne Jacquemier, Frédérique Penault-Llorca, Laurent Arnould
• Journal: European journal of cancer (Oxford, England : 1990) (Eur J Cancer) Vol. 42 Issue 17 Pg. 2946-53 (Nov 2006) ISSN: 0959-8049 [Print] England
• PMID: 16989997 (Publication Type: Journal Article, Multicenter Study)

Chemical References

• Receptor, ErbB-2

Topics

• Adult
• Aged
• Aged, 80 and over
• Breast Neoplasms (metabolism, pathology)
• Carcinoma, Ductal, Breast (metabolism, pathology)
• Female
• Humans
• Immunohistochemistry (standards)
• Middle Aged
• Observer Variation
• Receptor, ErbB-2 (metabolism)