Table 1. Phosphorylation status of ErbB2-Y1248 for trastuzumab non-responders and trastuzumab responders in trastuzumab neoadjuvant settings.
| Progress or residual disease after neoadjuvant trastuzumab treatment (non-responders) | ||
|---|---|---|
| Subject | ErbB2-pY1248 staining | Result |
| Case 1 | + | Negative |
| Case 2 | +/++ | Negative |
| Case 3 | 0 | Negative |
| Case 4 | +++ | Positive |
| Case 5 | + | Negative |
| Complete or near-complete pathological remission after neoadjuvant trastuzumab treatment (responders) | ||
| Subject | ErbB2-pY1248 staining | Result |
| Case 6 | +++ | Positive |
| Case 7 | +++ | Positive |
| Case 8 | +++ | Positive |
| Case 9 | +++ | Positive |
| Case 10 | +/++ | Negative |
ErbB2 IHC results were interpreted based on the most recent CAP/ASCO guideline.42 Positive cases were those with uniform, intense and complete membrane staining in greater than 30% of the invasive tumor cells (Score 3+). Negative cases were defined as those with either no staining (Score 0) or weak, incomplete membrane staining in less than or equal to 30% of cells, or complete membrane staining that was either non-uniform or weak in intensity, but with obvious circumferential distribution in at least 10% of tumor cells (Score 2+).