Table 2.
Clinical and Pathological Features of BCBM Patients in the Study Cohort
| Variables | Total Cohort | Training Cohort | Validation Cohort | p |
|---|---|---|---|---|
| n=223 | n=161 | n=62 | ||
| Age (%) | ||||
| <64 years | 151 (67.7) | 106 (65.8) | 45 (72.6) | 0.234 |
| 64–76 years | 56 (25.1) | 45 (28.0) | 11 (17.7) | |
| >76 years | 16 (7.2) | 10 (6.2) | 6 (9.7) | |
| Tumour site (%) | ||||
| Npple/central | 21 (9.4) | 16 (9.9) | 5 (8.1) | 0.808 |
| Upper-inner | 26 (11.7) | 21 (13.0) | 5 (8.1) | |
| Lower-inner | 7 (3.1) | 5 (3.1) | 2 (3.2) | |
| Upper-outer | 48 (21.5) | 34 (21.1) | 14 (22.6) | |
| Lower-outer | 15 (6.7) | 9 (5.6) | 6 (9.7) | |
| Others | 106 (47.5) | 76 (47.2) | 30 (48.4) | |
| Laterality (%) | ||||
| Left | 110 (49.3) | 87 (54.0) | 23 (37.1) | 0.034 |
| Right | 113 (50.7) | 74 (46.0) | 39 (62.9) | |
| Histology (%) | ||||
| Duct | 173 (77.6) | 125 (77.6) | 48 (77.4) | 0.855 |
| Lobular | 27 (12.1) | 19 (11.8) | 8 (12.9) | |
| Duct+lobular | 7 (3.1) | 6 (3.7) | 1 (1.6) | |
| Others | 16 (7.2) | 11 (6.8) | 5 (8.1) | |
| Grade (%) | ||||
| Grade1 | 21 (9.4) | 13 (8.1) | 8 (12.9) | 0.496 |
| Grade2 | 111 (49.8) | 80 (49.7) | 31 (50.0) | |
| Grade3 | 88 (39.5) | 65 (40.4) | 23 (37.1) | |
| Grade4 | 3 (1.3) | 3 (1.9) | 0 (0.0) | |
| Summary stage (%) | ||||
| Regional | 1 (0.4) | 1 (0.6) | 0 (0.0) | 1 |
| Distant | 222 (99.6) | 160 (99.4) | 62 (100.0) | |
| T_stage (%) | ||||
| T1 | 40 (17.9) | 30 (18.6) | 10 (16.1) | 0.849 |
| T2 | 82 (36.8) | 61 (37.9) | 21 (33.9) | |
| T3 | 37 (16.6) | 26 (16.1) | 11 (17.7) | |
| T4 | 64 (28.7) | 44 (27.3) | 20 (32.3) | |
| N_stage (%) | ||||
| N0 | 44 (19.7) | 27 (16.8) | 17 (27.4) | 0.328 |
| N1 | 117 (52.5) | 87 (54.0) | 30 (48.4) | |
| N2 | 28 (12.6) | 22 (13.7) | 6 (9.7) | |
| N3 | 34 (15.2) | 25 (15.5) | 9 (14.5) | |
| Surgprimsite (%) | ||||
| No | 145 (65.0) | 109 (67.7) | 36 (58.1) | 0.232 |
| Yes | 78 (35.0) | 52 (32.3) | 26 (41.9) | |
| Tumoursize (%) | ||||
| <2 cm | 41 (18.4) | 27 (16.8) | 14 (22.6) | 0.565 |
| 2~5 cm | 102 (45.7) | 74 (46.0) | 28 (45.2) | |
| >5 cm | 80 (35.9) | 60 (37.3) | 20 (32.3) | |
| Subtype (%) | ||||
| HR-/HER2- | 12 (5.4) | 10 (6.2) | 2 (3.2) | 0.069 |
| HR-/HER2+ | 10 (4.5) | 5 (3.1) | 5 (8.1) | |
| HR+/HER2- | 167 (74.9) | 126 (78.3) | 41 (66.1) | |
| HR+/HER2+ | 34 (15.2) | 20 (12.4) | 14 (22.6) | |
| ER (%) | ||||
| Negative | 22 (9.9) | 15 (9.3) | 7 (11.3) | 0.848 |
| Positive | 201 (90.1) | 146 (90.7) | 55 (88.7) | |
| PR (%) | ||||
| Negative | 52 (23.3) | 40 (24.8) | 12 (19.4) | 0.489 |
| Positive | 171 (76.7) | 121 (75.2) | 50 (80.6) | |
| HER2 (%) | ||||
| Negative | 179 (80.3) | 136 (84.5) | 43 (69.4) | 0.019 |
| Positive | 44 (19.7) | 25 (15.5) | 19 (30.6) | |
| Month (median [IQR]) | 29.00 [16.00, 46.00] | 30.00 [16.00, 46.00] | 24.00 [16.00, 49.00] | 0.649 |
Abbreviations: HER2, human epidermal growth factor receptor 2; ER, estrogen receptor; PR, progesterone receptor.