Table 4.
Comparison of tumor characteristics according to the response to neoadjuvant chemotherapy.
| Responder Group (n = 208) | Non-Responder Group (n = 38) | ||||
|---|---|---|---|---|---|
| Characteristics | Number | % | Number | % | p-Value |
| Pathology | 0.001 | ||||
| IDC | 201 | 96.60% | 31 | 81.60% | |
| ILC | 2 | 1.00% | 3 | 7.90% | |
| Mucinous | 2 | 1.00% | 3 | 7.90% | |
| Others | 3 | 1.40% | 1 | 2.60% | |
| T stage | 0.116 | ||||
| T1 | 42 | 20.20% | 4 | 10.50% | |
| T2 | 120 | 57.70% | 19 | 50.00% | |
| T3 | 26 | 12.50% | 8 | 21.10% | |
| T4 | 20 | 9.60% | 7 | 18.40% | |
| N stage | 0.076 | ||||
| N0 | 52 | 25.00% | 6 | 15.80% | |
| N1 | 87 | 41.80% | 11 | 28.90% | |
| N2 | 37 | 17.80% | 12 | 31.60% | |
| N3 | 32 | 15.40% | 9 | 23.70% | |
| Stage | 0.003 | ||||
| I | 9 | 4.30% | 0 | 0.00% | |
| II | 112 | 53.90% | 11 | 28.90% | |
| III | 87 | 41.80% | 27 | 71.10% | |
| Operation | <0.001 | ||||
| Breast-conserving surgery | 120 | 57.70% | 9 | 23.70% | |
| Modified radical mastectomy | 88 | 42.30% | 29 | 76.30% | |
| RT modality | 0.241 | ||||
| 3D CRT | 51 | 24.50% | 6 | 15.80% | |
| IMRT | 157 | 75.50% | 32 | 84.20% | |
| Dose scheme | 0.354 | ||||
| 180 cGy per fraction | 189 | 90.90% | 37 | 97.40% | |
| 200 cGy per fraction | 8 | 3.80% | 0 | 0.00% | |
| 267 cGy per fraction | 11 | 5.30% | 1 | 2.60% | |
| ER | 0.236 | ||||
| Negative | 87 | 41.80% | 12 | 31.60% | |
| Positive | 121 | 58.20% | 26 | 68.40% | |
| PR | 0.874 | ||||
| Negative | 145 | 69.70% | 26 | 68.40% | |
| Positive | 63 | 30.30% | 12 | 31.60% | |
| HER2 | 0.296 | ||||
| Negative | 141 | 67.80% | 29 | 76.30% | |
| Positive | 67 | 32.20% | 9 | 23.70% | |
| Ki-67 | 0.001 | ||||
| <15 | 92 | 44.20% | 20 | 52.60% | |
| ≥15 | 60 | 28.80% | 18 | 47.40% | |
| Unknown | 56 | 27.00% | 0 | 0.00% | |
| Chemotherapy regimen | <0.001 | ||||
| Adriamycin based | 1 | 0.50% | 4 | 10.50% | |
| Adriamycin and taxol based | 138 | 66.30% | 23 | 60.50% | |
| Taxol based | 5 | 2.40% | 3 | 7.90% | |
| Trastuzumab based | 64 | 30.80% | 8 | 21.10% | |
| Selective estrogen receptor modulator | 0.162 | ||||
| No | 117 | 56.25% | 26 | 68.40% | |
| Yes | 91 | 43.75% | 12 | 31.60% | |
| Aromatase inhibitor | 0.560 | ||||
| No | 185 | 88.90% | 35 | 92.10% | |
| Yes | 23 | 11.10% | 3 | 7.90% | |
Abbreviations: IDC, Invasive ductal carcinoma; ILC, Invasive lobular carcinoma; T stage, Tumor stage; N stage, Node stage; RT, Radiotherapy; 3D CRT, 3-dimensional conformal radiotherapy; IMRT, Intensity-modulated radiation therapy; ER, Estrogen receptor; PR, Progesterone receptor, HER2, Human epidermal growth factor receptor 2.