[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.
| Year | 0 n (%) | 1 n (%) | 2 n (%) | 3 n (%) | Total |
| 2004 | 590 (43.8) | 426 (31.62) | 50 (3.7) | 281 (20.86) | 1347 |
| 2005 | 1027 (48) | 602 (28) | 156 (7) | 349 (17) | 2134 |
| 2006 | 2407 (53.5) | 1103 (24.5) | 261 (5.8) | 729 (16.2) | 4500 |
| 2007 | 3327 (51.9) | 1711 (26.7) | 313 (4.9) | 1064 (16.6) | 6415 |
| 2008 | 4234 (53.39) | 2060 (25.98) | 376 (4.74) | 1260 (15.89) | 7930 |
| 2009 | 2695 (54.49) | 1189 (24.92) | 230 (4.82) | 657 (13.77) | 4771 |