Table 1.
Patient and tumor characteristics of young patients with node-negative triple-negative breast cancer
| Characteristic | All patients |
|---|---|
| N (%) | |
| Total | 485 (100) |
| Age at diagnosis, median years (IQR) | 35 (32-38) |
| T-stage, n (%) | |
| pT1 | 285 (58.8) |
| pT2 | 188 (38.8) |
| pT3 | 10 (2.1) |
| Unknown | 2 (0.4) |
| Histologic grade, n (%) | |
| 1-2 | 70 (14.4) |
| 3 | 415 (85.6) |
| Histological subtype, n (%) | |
| Carcinoma NST | 445 (91.8) |
| Metaplastic carcinoma | 27 (5.6) |
| Othera | 13 (2.7) |
| sTILs percentage, median (IQR) | 25 (5-70) |
| sTILs percentage | |
| <30% | 247 (50.9) |
| 30%-75% | 127 (26.2) |
| ≥75% | 107 (22.1) |
| Unknown | 4 (0.8) |
| ER status | |
| ER-negative (0%) | 461 (95.1) |
| ER low-positive (1%-9%) | 24 (4.9) |
| HER2 statusb | |
| HER2-negative | 441 (90.9) |
| HER2-low | 44 (9.1) |
| AR status | |
| Negative (0%) | 367 (75.7) |
| Positive (≥1%) | 80 (16.5) |
| Unknown | 38 (7.8) |
| LVI | |
| Absent | 429 (88.5) |
| Present | 56 (11.5) |
| Pushing borders | |
| Absent | 186 (38.4) |
| <25%c | 56 (11.5) |
| 25%-75%c | 78 (16.1) |
| ≥75%c | 152 (31.3) |
| Unknown | 13 (2.7) |
| Central necrosis | |
| Absent | 234 (48.2) |
| Present | 251 (51.8) |
| Fibrotic focus | |
| Absent | 346 (71.3) |
| Present | 139 (28.7) |
| Tumor BRCA1 status | |
| Wild-type | 303 (62.5) |
| Mutated | 114 (23.5) |
| Unknown | 68 (14.0) |
| Local treatment, n (%) | |
| Lumpectomy | 324 (66.8) |
| Mastectomy | 152 (31.3) |
| Surgery not specified | 9 (1.9) |
| Radiotherapy | |
| No | 141 (29.1) |
| Yes | 344 (70.9) |
AR, androgen receptor; ER, estrogen receptor; HER2, human epidermal growth factor receptor 2; IQR, interquartile range; LVI, lymphovascular invasion; NST, no special type; sTILs, stromal tumor-infiltrating lymphocytes.
a
Includes: adenoid cystic carcinoma, apocrine carcinoma, invasive cribriform carcinoma, ductolobular carcinoma, invasive papillary carcinoma, invasive lobular carcinoma and invasive micropapillary carcinoma.
b
HER2-low is defined as HER2 IHC1+ or IHC2+ with negative in situ hybridization.
c
Of tumor perimeter.