Table 1.
Demographics and clinicopathologic characteristics of the cohort with BCLM.
| Variables | Total cohort | Training cohort | Validation cohort |
|---|---|---|---|
| No. (%) | No. (%) | No. (%) | |
| Year of diagnosis | |||
| 2010-2012 | 590 (50.3) | 401 (48.7) | 189 (54.2) |
| 2013-2015 | 583 (49.7) | 423 (51.3) | 160 (45.8) |
| Age | |||
| 18—56 years | 570 (48.6) | 401 (48.7) | 169 (48.4) |
| ≥56 years | 603 (51.4) | 423 (51.3) | 180 (51.6) |
| Race | |||
| White | 840 (71.6) | 601 (72.9) | 239 (68.5) |
| Black | 203 (17.3) | 127 (15.4) | 76 (21.8) |
| Other | 130 (11.1) | 96 (11.7) | 34 (9.7) |
| Marital status | |||
| Married | 566 (48.3) | 409 (49.6) | 157 (45.0) |
| Unmarried | 607 (51.7) | 415 (50.4) | 192 (55.0) |
| Grade | |||
| Well differentiated | 457 (39.0) | 316 (38.4) | 141 (40.4) |
| Poorly differentiated | 716 (61.0) | 508 (61.6) | 208 (59.6) |
| Laterality | |||
| Left | 630 (53.7) | 453 (55.0) | 177 (50.7) |
| Right | 543 (46.3) | 371 (45.0) | 172 (49.3) |
| T stage | |||
| T1 | 118 (10.1) | 94 (11.4) | 24 (6.9) |
| T2 | 408 (34.8) | 275 (33.4) | 133 (38.1) |
| T3 | 235 (20.0) | 164 (19.9) | 71 (20.3) |
| T4 | 412 (35.1) | 291 (35.3) | 121 (34.7) |
| N stage | |||
| N0 | 213 (18.2) | 155 (18.8) | 58 (16.6) |
| N1 | 626 (53.4) | 435 (52.8) | 191 (54.7) |
| N2 | 157 (13.4) | 105 (12.7) | 52 (14.9) |
| N3 | 177 (15.1) | 129 (15.7) | 48 (13.8) |
| Surgery | |||
| No | 807 (68.8) | 565 (68.6) | 242 (69.3) |
| Yes | 366 (31.2) | 259 (31.4) | 107 (30.7) |
| Radiation therapy | |||
| No | 833 (71.0) | 590 (71.6) | 243 (69.6) |
| Yes | 340 (29.0) | 234 (28.4) | 106 (30.4) |
| Chemotherapy | |||
| No | 324 (27.6) | 232 (28.2) | 92 (26.4) |
| Yes | 849 (72.4) | 592 (71.8) | 257 (73.6) |
| CS tumor size | |||
| <50mm | 610 (52.0) | 426 (51.7) | 184 (52.7) |
| ≥50mm | 563 (48.0) | 398 (48.3) | 165 (47.3) |
| CS Tumor Size/Ext Eval | |||
| 0 | 370 (31.5) | 268 (32.5) | 102 (29.2) |
| 1—6 | 803 (68.5) | 556 (67.5) | 247 (70.8) |
| Tumor subtypes | |||
| Luminal A | 501 (42.7) | 338 (41.0) | 163 (46.7) |
| Luminal B | 271 (23.1) | 199 (24.2) | 72 (20.6) |
| HER2 enriched | 200 (17.1) | 142 (17.2) | 58 (16.6) |
| Triple-negative breast cancer | 201 (17.1) | 145 (17.6) | 56 (16.1) |
| Bone metastatic | |||
| No | 505 (43.1) | 362 (43.9) | 142 (41.0) |
| Yes | 668 (56.9) | 462 (56.1) | 206 (59.0) |
| Brain metastatic | |||
| No | 1089 (92.8) | 766 (93.0) | 323 (92.5) |
| Yes | 84 (7.2) | 58 (7.0) | 26 (7.5) |
| Lung metastatic | |||
| No | 767 (65.4) | 535 (64.9) | 232 (66.5) |
| Yes | 406 (34.6) | 289 (35.1) | 117 (33.5) |
HER2, Human epidermal growth factor receptor 2. For marital status, unmarried consists of single, divorced, separated, and widowed. For race, ‘other’ includes American Indian, AK Native, Asian, and Pacific Islander. Laterality is defined as the laterality of tumor primary sites. For grade, well differentiated including Grade Ⅰ and Ⅱ, poorly differentiated including Grade Ⅲ and Ⅳ.