TABLE 2.
Univariate and multivariable analysis of factors associated with pCR (T0/is N0) (data are n [%])
| Entire cohort (n = 1383) |
No pCR (n = 1017) |
pCR (n = 366) |
Univariate | Multivariable | |||
|---|---|---|---|---|---|---|---|
| p | OR | 95% CI | p | ||||
| Age category | 0.6 | 0.50 | |||||
| ≤ 40 years | 300 (22%) | 214 (21%) | 86 (23%) | ref | |||
| 41–60 years | 772 (56%) | 571 (56%) | 201 (55%) | 0.97 | 0.64–1.50 | ||
| ≥ 61 years | 311 (22%) | 232 (23%) | 79 (22%) | 0.77 | 0.46–1.30 | ||
| Histology | < 0.001 | 0.60 | |||||
| Ductal | 1244 (92%) | 906 (90%) | 338 (96%) | ref | |||
| Lobular/mixed | 99 (7.3%) | 89 (8.8%) | 10 (2.8%) | 0.67 | 0.23–1.66 | ||
| Other | 16 (1.2%) | 12 (1.2%) | 4 (1.1%) | 1.56 | 0.30–6.43 | ||
| Histologic grade | < 0.001 | < 0.001 | |||||
| Poorly differentiated | 964 (70%) | 638 (63%) | 326 (90%) | ref | |||
| Moderately differentiated | 391 (28%) | 354 (35%) | 37 (10%) | 0.31 | 0.18–0.50 | ||
| Well differentiated | 21 (1.5%) | 21 (2.1%) | 0 (0%) | 0.00 | |||
| Lymphovascular invasion | 406 (39%) | 361 (43%) | 45 (21%) | < 0.001 | 0.46 | 0.31–0.68 | < 0.001 |
| Clinical tumor stage | 0.017 | 0.081 | |||||
| T0-T1 | 210 (15%) | 145 (14%) | 65 (18%) | ref | |||
| T2 | 766 (55%) | 553 (54%) | 213 (58%) | 0.89 | 0.53–1.52 | ||
| T3 | 271 (20%) | 219 (22%) | 52 (14%) | 0.50 | 0.26–0.95 | ||
| T4 | 136 (9.8%) | 100 (9.8%) | 36 (9.8%) | 0.93 | 0.45–1.90 | ||
| Clinical nodal stage, n (%) | 0.001 | 0.40 | |||||
| N0 | 449 (32%) | 313 (31%) | 136 (37%) | ref | |||
| N1 | 813 (59%) | 626 (62%) | 187 (51%) | 0.86 | 0.60–1.26 | ||
| N2–3 | 121 (8.7%) | 78 (7.7%) | 43 (12%) | 1.30 | 0.69–2.40 | ||
| Tumor subtype, n (%) | < 0.001 | < 0.001 | |||||
| TN | 394 (28%) | 275 (27%) | 119 (33%) | ref | |||
| HR+ HER2− | 487 (35%) | 453 (45%) | 34 (9.3%) | 0.29 | 0.16–0.52 | ||
| HER2+ | 502 (36%) | 289 (28%) | 213 (58%) | 2.55 | 1.76–3.75 | ||
| NAC regimena, n (%) | 0.093 | - | |||||
| ACT-based | 1268 (92%) | 939 (93%) | 329 (91%) | - | - | - | |
| CMF-based | 9 (0.7%) | 9 (0.9%) | 0 (0%) | - | - | - | |
| Other | 5 (0.4%) | 3 (0.3%) | 2 (0.6%) | - | - | - | |
| Taxane-based | 95 (6.9%) | 64 (6.3%) | 31 (8.6%) | - | - | - | |
| NAC included carboplatin a | 172 (12%) | 116 (11%) | 56 (15%) | 0.057 | - | - | - |
a
NAC regimen was not included in the multivariable model, as it was not significant on univariate analysis
pCR pathologic complete response; OR odds ratio. CI confidence interval. TN triple-negative. HR hormone receptor. HER2 human epidermal growth factor receptor 2. NAC neoadjuvant chemotherapy. ACT doxorubicin and cyclophosphamide followed by a taxane. CMF cyclophosphamide, methotrexate, 5-fluorouracil