Table 1.
The relationship between biomarker levels and whether a pathologic complete response (pCR) was achieved, adjusted for estrogen receptor status (all arms pooled)
| Biomarker* | Patients achieving a pCR in the ‘high’ or ‘yes’ subgroup, n/N (%) | Patients achieving a pCR in the ‘low’ or ‘no’ subgroup, n/N (%) | P value (chi-squared test) |
|---|---|---|---|
| HER2 membrane |
115/159 (72.3) |
24/66 (36.4) |
0.00002 |
| HER3 membrane |
32/58 (55.2) |
38/54 (70.4) |
0.32864 |
| IGF-1R membrane |
27/57 (47.4) |
44/56 (78.6) |
0.05313 |
| EGFR membrane |
21/36 (58.3) |
48/73 (65.8) |
0.01037 |
| PTEN cytoplasmic |
59/92 (64.1) |
11/21 (52.4) |
0.04968 |
| PTEN nuclear |
39/60 (65.0) |
31/53 (58.5) |
0.22086 |
|
EGFR mRNA |
65/98 (66.3) |
60/98 (61.2) |
0.65169 |
|
HER2 mRNA |
78/106 (73.6) |
53/104 (51.0) |
0.00060 |
|
HER3 mRNA |
60/105 (57.1) |
71/105 (67.6) |
0.89283 |
|
Amphiregulin mRNA |
55/95 (57.9) |
66/95 (69.5) |
0.42068 |
|
TOP2A |
35/62 (56.5) |
83/130 (63.9) |
0.57728 |
|
c-Myc |
40/61 (65.6) |
66/106 (62.3) |
0.52483 |
| Amphiregulin |
68/102 (66.7) |
62/101 (61.4) |
0.29743 |
| EGF |
65/102 (63.7) |
65/101 (64.4) |
0.83132 |
| sHER2 |
68/102 (66.7) |
62/101 (61.4) |
0.89167 |
| TGFα |
60/102 (58.8) |
70/101 (69.3) |
0.16475 |
| PIK3CA mutation | 19/39 (48.7) | 81/126 (64.3) | 0.17160 |
*All biomarkers assessed by IHC are represented by H-scores. EGF, epidermal growth factor; EGFR, epidermal growth factor receptor; HER, human epidermal growth factor receptor; IGF-1R, insulin-like growth factor 1 receptor; PIK3CA, phosphoinositide-3-kinase, catalytic alpha polypeptide; PTEN, phosphatase and tensin homolog; sHER2, serum HER2; TGFα, transforming growth factor alpha; TOP2A, topoisomerase 2 alpha.