local vs central Her2 testing?

"Initial findings from the Breast Cancer Intergroup study N9831 of adjuvant trastuzumab indicated that only 74% of cases found to be HER2+ upon local testing (IHC 3+ or FISH+) were confirmed to be positive on central testing.18 This trial was subsequently amended to require central confirmation of HER2+ status, and over time, a higher level of concordance between local and central testing has been seen. Currently, when local and central evaluations used the same methodology, concordance is 87.0% for FISH and 81% for the HercepTest™.19 It is interesting that among cases tested locally by FISH, 13% were still not confirmed on central FISH testing."

Anyone know what the difference between local and central testing is and which is done more commonly?

[AlaskaAngel]

Basically what the researchers in the studies had to do was set some guidelines for the patients who were going to be in the clinical trials because having so many inaccurate HER2 testing results would mess up the studies. Labs that do a high volume of the tests on a steady basis are most likely to have accurate results and I gather that those conducting the studies ended up specifying 6 or 7 labs in central locations (places where there are lots of cancer patients and research going on) where could be used for testing patients for the studies.

So the basic idea is, don't have your testing done in a small facility that occasionally does the test because it might tend to be more subjective and less accurate, and try to have it done in a central major lab near or connected to research facilities where personnel probably are generally more qualified and more frequent periodic testing for accuracy is done to maintain standards.