Table 2. Patient and tumour characteristics and interim MRI response (after three courses of neoadjuvant chemotherapy).
| MRI favourable response (N=164) | MRI unfavourable response (N=82) | ||
|---|---|---|---|
| Characteristic | N (%) | N (%) | P-value |
| T-stage |
|
|
0.885 |
| cT1/cT2 | 112 (68) | 57 (70) | |
| cT3/cT4 |
52 (32) |
25 (31) |
|
| N-stage |
|
|
0.011 |
| cN negative | 25 (15) | 24 (29) | |
| cN positive |
139 (85) |
58 (71) |
|
| Histology |
|
|
0.112 |
| Lobular | 26 (18) | 7 (9) | |
| Ductal | 120 (82) | 70 (91) | |
| Other |
18 |
5 |
|
| Age (years) |
|
|
0.412 |
| <50 | 101 (62) | 46 ((56) | |
| ⩾50 |
63 (38) |
36 (44) |
|
| Endocrine responsiveness |
|
|
0.585 |
| Incomplete (ER or PR <50%) | 74 (47) | 35 (43) | |
| High (ER and PR ⩾50%) | 83 (53) | 46 (57) | |
| ND |
7 |
1 |
|
| Surrogate intrinsic subtype (Ki-67) |
|
|
0.510 |
| Luminal A (<14) | 82 (66) | 46 (72) | |
| Luminal B (⩾14) | 42 (34) | 18 (28) | |
| ND |
40 |
18 |
|
| Surrogate intrinsic subtype (grade) |
|
|
1.0 |
| Luminal A (1/2) | 73 (79) | 36 (78) | |
| Luminal B (3) | 20 (22) | 10 (22) | |
| ND | 71 | 36 |
Abbreviations: ER=oestrogen receptor; MRI=magnetic resonance imaging; ND=not done; PR=progesterone receptor.
A reduction of over 25% of the late enhancement diameter on the second contrast-enhanced MRI was regarded as a favourable response (Loo et al, 2008).