Table 2.
Patient and tumor characteristics
| No. | % | |
|---|---|---|
| Total no. of tumors | 139 | 100 |
| Patient mean age at diagnosis (years) | 59 | – |
| Histological subtype | ||
| Ductal/no special type | 112 | 80.6 |
| Lobular | 16 | 11.5 |
| Other | 11 | 7.9 |
| Nottingham histological grade | ||
| Grade 1 | 21 | 15.1 |
| Grade 2 | 72 | 51.8 |
| Grade 3 | 44 | 31.7 |
| Unclassified | 2 | 1.4 |
| Tumor size (mm) and pT* | ||
| ≤ 20, pT1 | 55 | 39.6 |
| > 20 and ≤ 50, pT2 | 76 | 54.7 |
| > 50, pT3 | 8 | 5.8 |
| No. of positive lymph nodes and pN* | ||
| 0, pN0 | 76 | 54.7 |
| 1–3, pN1 | 45 | 32.4 |
| 4–9, pN2 | 13 | 9.4 |
| ≥ 10, pN3 | 5 | 3.6 |
| Estrogen receptor (%) | ||
| ≥ 1 and < 10 | 0 | 0.0 |
| ≥ 10 | 132 | 95.0 |
| Positive by other method | 7 | 5.0 |
| Progesterone receptor (%) | ||
| < 20 | 36 | 25.9 |
| ≥ 20 | 99 | 71.2 |
| Positive by other method | 4 | 2.9 |
| Ki67 (%) | ||
| < 20 | 59 | 42.4 |
| ≥ 20 | 70 | 50.4 |
| Unknown numerical value | 10 | 7.2 |
| IHC-based surrogate subtype | ||
| Luminal A-like | 47 | 33.8 |
| Luminal B-like (HER2−) | 82 | 59.0 |
| LumA/LumB unknown Ki67 value | 10 | 7.2 |
| PAM50 intrinsic subtype | ||
| Luminal A | 79 | 56.8 |
| Luminal B | 30 | 21.6 |
| HER2-enriched | 1 | 0.7 |
| Basal-like | 1 | 0.7 |
| Unclassified | 28 | 20.1 |
| Neoadjuvant treatment | ||
| Endocrine therapy | 1 | 0.72 |
| Adjuvant treatment | ||
| Chemotherapy | 54 | 38.8 |
| Endocrine therapy | 118 | 84.9 |
| Radiotherapy | 89 | 64.0 |
| Anti-HER2 therapy | 0 | 0.0 |
| Unclassified | 18 | 12.9 |
| Outcome | ||
| Patients with recurrence at end follow-up | 28 | 20.1 |
| 5-year recurrence-free survival rate (%) | 82.9 | |
| 10-year recurrence-free survival rate (%) | 57.1 | |
| Patients dead at end follow-up | 20 | 14.4 |
| 5-year overall survival rate (%) | 94.3 | |
| 10-year overall survival rate (%) | 67.7 |
*Pathologic T stage (pT) for invasive tumor and pathologic N stage (pN) for regional lymph nodes according to AJCC Breast Cancer Staging 7th Edition (TNM 7)