[195] HER2 Diagnosis Program in Argentina with a Standardized and Reproducible Technique: Variation in Positive Rates throughout the Years

I Frahm, G Acosta Haab, S Sarancone, Grupo Her2, V Caceres. Sanatorio Mater Dei, Buenos Aires, Argentina; Hospital Maria Curie, Buenos Aires, Argentina; Labotatorio Quantum, Rosario, Santa Fe, Argentina; Programa Nacional de Diagnostico de HER2, Argentina; Productos Roche, Tigre, Buenos Aires, Argentina

Background: HER2 testing has a key role in the management of breast cancer, so we settled a National testing Program to permit access to standardized Her 2 detection all over the country. In August 2003, 13 pathologists formed a cooperative group and created a national framework to train and set HER2 diagnostic centres in each country region. A coordinator responsible for coaching and evaluating centres and two technical consultants in charge of quality control and technique standardization were designated. External controls (i.e. CAP, Nordi QC, UK-NEQAST) were also implemented. In February 2004, the program was launched Aim: Report our findings from February 2004 to July 2009.
Design: HER2 over-expression was analyzed by Inmuno-Histo-Chemical (IHC) using policlonal antibody anti Her 2 (DAKO), microwave antigenic recovery, detection system EnVision (Dako) and developed with diaminobenzidine. Results were interpreted as hercepTest® guideline's Following ASCO-CAP recommendations HER 2 equivocal, were re-tested with FISH.
Results: 27097 IHQ tests were performed and 773 were re-tested by FISH: 343 (44%) amplified.

HER 2 over-expression
Year0 n (%)1 n (%)2 n (%)3 n (%)Total
2004590 (43.8)426 (31.62)50 (3.7)281 (20.86)1347
20051027 (48)602 (28)156 (7)349 (17)2134
20062407 (53.5)1103 (24.5)261 (5.8)729 (16.2)4500
20073327 (51.9)1711 (26.7)313 (4.9)1064 (16.6)6415
20084234 (53.39)2060 (25.98)376 (4.74)1260 (15.89)7930
20092695 (54.49)1189 (24.92)230 (4.82)657 (13.77)4771

Conclusions: HER2 National Program enabled country-wide HER2 testing. HER2 prevalence in our population drops off along the years and might be linked to the increase of early breast cancer testing and technique standardization. Internal quality control, done by the Advisory Board, as well as independent and external quality control, carried out by the CAP, NordiQC and UK-NEQAST have assured accurate outcome We presented performance, interpretation, and technical issues guides for HER2 testing based on our experience, endorsed by Argentinean Society of Pathology.
Category: Breast

Tuesday, March 23, 2010 1:00 PM

Poster Session IV # 6, Tuesday Afternoon


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