Patient and tumour characteristics
| Characteristic | Patients with cancer n = 242 | Patients undergoing CPM n = 69 | Patients undergoing BPM n = 26 |
|---|---|---|---|
| Age, yr, mean | 52 | 51.4 | 49.7 |
| Female, n | 242 | 69 | 26 |
| Size of lesion on imaging, mm,* mean | 21.6 | 7.54 | 0 |
| Tumour histology | |||
| DCIS, n | 41 | 5 | 1 |
| Size of DCIS, mm, mean (range) | 21.7 (0–85) | 4.3 (1–9) | 1 |
| Invasive cancer, n | 201 | 1 | — |
| Size of invasive cancer, mm, mean (range) | 16.9 (0–57) | 1 | — |
| T stage, n | |||
| Tis | 41 | 5 | 1 |
| T1 | 106 | — | — |
| T2 | 44 | — | — |
| T3 | 3 | — | — |
| T4 | — | — | — |
| Nottingham grade, n | |||
| I | 42 | 5 | 1 |
| II | 84 | — | — |
| III | 68 | — | — |
| Axillary procedure, n | |||
| SLNB | 185 | 3 | — |
| ALND | 22 | — | — |
| None | 35 | 66 | 26 |
| Nodal status, n | |||
| Node positive | 57/207 | — | — |
| Node negative | 150/207 | 3/3 | — |
| Lymphovascular invasion, n | |||
| Yes | 52/242 | 1/6 | — |
| No | 108/242 | — | 1/1 |
| Invasive tumour subtype, n | |||
| HR+/HER2− | 63/201 | 2/6 | — |
| HR+/HER2+ | 10/201 | 1/6 | — |
| HR−/HER2− | 13/201 | 1/6 | — |
| HR−/HER2+ | 9/201 | — | — |
| Median follow-up, mo | 33.7 | 44.1 | — |
| Neoadjuvant therapy, n | |||
| Yes | 31 | — | — |
| No | 211 | 69 | 26 |
| Adjuvant therapy, n | |||
| Chemotherapy | 68 | — | — |
| Radiation therapy | 70 | — | — |
| Endocrine therapy | 137 | — | — |
ALND = axillary lymph node dissection; BPM = bilateral prophylactic mastectomy; CPM = contralateral prophylactic mastectomy; DCIS = ductal carcinoma in situ; HER2 = human epidermal growth factor receptor 2; HR = hormone receptor; SD = standard deviation; SLNB = sentinel lymph node biopsy.
↵* Largest size modality of imaging was used among ultrasonography, magnetic resonance imaging and mammogram.