From: Assessment of HER2 status in breast cancer: overall positivity rate and accuracy by fluorescence in situ hybridization and immunohistochemistry in a single institution over 12 years: a quality control study
IHC
FISH
0
1+
2+
3+
Non amplified
361
567
384
29
(> 99%)
(95%)
(16%)
Amplified
3
20
155
(< 1%)
(5%)
(84%)
Total (n = 1522 )
364
570
404
184
(100%)