Table 1. Associations between the clinicopathological variables and pCR.
| Characteristics | Study set (n=443) | Validation set (n=296) | |||||
|---|---|---|---|---|---|---|---|
| Non-pCR | pCR | P-value | Non-pCR | pCR | P-value | ||
| Age | ≤ 40y | 98(86.0%) | 16(14.0%) | 0.746 | 44(84.6%) | 8(15.4%) | 0.824 |
| >40y | 288(87.5%) | 41(12.5%) | 210(86.1%) | 34(13.9%) | |||
| Tumor size | > 5cm | 77(93.9%) | 5(6.1%) | 0.044 | 41(85.4%) | 7(14.6%) | 0.774 |
| ≤ 5cm | 309(85.6%) | 52(14.4%) | 213(85.9%) | 35(14.1%) | |||
| LN status | Negative | 84(86.6%) | 13(13.4%) | 0.864 | 109(84.5%) | 20(15.5%) | 0.863 |
| Positive | 302(87.3%) | 44(12.7%) | 145(86.8%) | 22(13.2%) | |||
| TNM stage | I | 7(87.5%) | 1(12.5%) | 0.316 | 46(85.2%) | 8(14.8%) | 0.505 |
| II | 148(85.1%) | 26(14.9%) | 131(85.1%) | 23(14.9%) | |||
| III | 231(88.5%) | 30(11.5%) | 77(87.5%) | 11(12.5%) | |||
| PR | Negative | 164(83.7%) | 32(16.3%) | 0.063 | 38(86.4%) | 6(13.6%) | 0.948 |
| Positive | 222(89.9%) | 25(10.1%) | 216(85.7%) | 36(14.3%) | |||
| HER2 | Negative | 247(89.8%) | 28(10.2%) | 0.04 | 195(85.5%) | 33(14.5%) | 0.418 |
| Positive | 139(82.7%) | 29(17.3%) | 59(86.8%) | 9(3.9%) | |||
| ki-67 | ≤14% | 128(88.9%) | 16(11.1%) | 0.545 | 126(87.5%) | 18(12.5%) | 0.468 |
| >14% | 258(86.2%) | 41(13.8%) | 128(84.2%) | 24(15.8%) | |||
| Grade | 1 | 56(86.2%) | 9(13.8%) | 0.231 | 20(87.0%) | 3(13.0%) | 0.256 |
| 2 | 168(90.3%) | 18(9.7%) | 107(89.9%) | 12(10.1%) | |||
| 3 | 162(84.4%) | 30(15.6%) | 127(82.5%) | 27(17.5%) | |||
| NAC | E-based | 93(87.7%) | 13(12.3%) | 0.52 | 86(92.5%) | 9(9.5%) | 0.160 |
| ET-based | 293(86.9%) | 44(13.1%) | 168(83.6%) | 33(16.4%) | |||
| Surgery | BCS | 116(81.70%) | 26(18.30%) | 0.023 | 97(75.8%) | 31(24.2%) | 0.012 |
| MRM | 270(89.70%) | 31(10.30%) | 156(93.4%) | 11(6.6%) | |||
| NPI | < 3.4 | 75(79.8%) | 19(20.2%) | 0.043 | 57(78.1%) | 16(21.9%) | 0.022 |
| 3.4∼5.4 | 197(88.7%) | 25(11.3%) | 123(85.4%) | 21(14.6%) | |||
| >5.4 | 114(89.8%) | 13(10.2%) | 74(93.7%) | 5(6.3%) | |||
| IHC4 score | Q1 | 88(79.3%) | 23(20.7%) | 0.012 | 84(80.0%) | 21(20.0%) | 0.047 |
| Q2 | 196(88.7%) | 25(11.3%) | 97(86.6%) | 15(13.4%) | |||
| Q3 | 102(91.9%) | 9(8.1%) | 73(92.4%) | 6(7.6%) | |||
Abbreviations: pCR, pathological complete response; LN, lymph node; ER, estrogen receptor; PR, progesterone receptor; HER2, human epidermal growth factor receptor 2; NAC, neoadjuvant chemotherapy; E-based, anthracycline-based regiment; ET, anthracycline and taxanes-based regiment; BCS, breast conserving surgery; MRM, mamomodified radical mastectomy.