Table 3.
Validation Data Set Discordant Cases
| Breast sample type | Tumor (%) | Inflammation | HER2 IHC | HER2 FISH HER2/CEP17 (HER2 CN, CEP17 CN) |
ERBB2 fold change (range) |
|---|---|---|---|---|---|
| Bx | 50 | Minimal | 2 | 2.0 (5.0, 2.4) | 1.4 (1.38 to 1.97) |
| Ex | 10 | Marked | 3 | 2.3 (4.7, 2.05) | 1.2 (−1.04 to 1.35) |
| Ex | 60 | Moderate | 2 (Focal) | Heterogeneous | 1.4 (1.34 to 1.72) |
| 10%: 3.2 (6.8, 2.1) | |||||
| 90%: 1.5 (3.0, 2.0) | |||||
| Ex | 60 | Moderate | 2 | 2.9 (4.9, 1.7) | 1.2 (−1.02 to 1.33) |
Bx, biopsy; CEP17, chromosome 17 centromere marker; CN, copy number; Ex, excision; FISH, fluorescence in situ hybridization; HER2, human epidermal growth factor receptor 2; IHC, immunohistochemistry.