Table 3: Relationship of IHC (determined according to ASCO/CAP 2013 or 2007) versus ISH (HER2/CEP17 ratio < 2.0: negative; ratio ≥ 2.0: positive).
| (a) ASCO/CAP 2013 | ||||
| ISH | ||||
| < 2.0 | ≤ 2.0 | Total | ||
| IHC | 0/1+ | 8 | 0 | 8 |
| 2+ | 18 | 5 | 23 | |
| 3+ | 3 | 7 | 10 | |
| Total | 29 | 12 | 41 | |
| (b) ASCO/CAP 2007 | ||||
| ISH | ||||
| < 2.0 | ≤ 2.0 | Total | ||
| IHC | 0/1+ | 8 | 0 | 8 |
| 2+ | 20 | 7 | 27 | |
| 3+ | 1 | 5 | 6 | |
| Total | 29 | 12 | 41 | |