Table 1.
Characteristics of patients with LABC in the training and validation group.
| Characteristics | Training cohort | Internal validation cohort | Overall | External validation cohort | T vs. IV | T vs. EV |
|---|---|---|---|---|---|---|
| (n = 15,917) | (n = 6,925) | (n = 22,842) | (n = 200) | P | P | |
| No. of patients (%) | No. of patients (%) | No. of patients (%) | No. of patients (%) | |||
| Age | 0.11 | 0.46 | ||||
| <40 | 1,665 (10.5) | 762 (11.0) | 2,427 (10.6) | 19 (9.5) | ||
| 40–59 | 7,776 (48.8) | 3,317 (47.9) | 11,093 (48.6) | 100 (50.0) | ||
| 60–79 | 5,235 (32.9) | 2,252 (32.5) | 7,487 (32.8) | 60 (30.0) | ||
| ≧80 | 1,241 (7.8) | 594 (8.6) | 1,835 (8.0) | 21 (10.5) | ||
| Race | 0.74 | <0.01 | ||||
| White | 11,778 (74.0) | 5,103 (73.7) | 16,881 (73.9) | 0 (0.0) | ||
| Black | 2,522 (15.8) | 1,125 (16.2) | 3,647 (16.0) | 0 (0.0) | ||
| Othersa | 1,617 (10.2) | 697 (10.1) | 2,314 (10.1) | 200 (100.0) | ||
| Sex | 0.14 | 0.52 | ||||
| Female | 15,717 (98.7) | 6,854 (99.0) | 22,571 (98.8) | 199 (99.5) | ||
| male | 200 (1.3) | 71 (1.0) | 271 (1.2) | 1 (0.5) | ||
| Laterality | 0.28 | 0.73 | ||||
| Left | 8,043 (50.5) | 3,489 (50.4) | 11,532 (50.5) | 100 (50.0) | ||
| Right | 7,871 (49.5) | 3,435 (49.6) | 11,306 (49.5) | 100 (50.0) | ||
| Bilateral | 3 (0.0) | 1 (0.0) | 4 (0.0) | 0 (0.0) | ||
| Marital status | 0.43 | 0.70 | ||||
| Married | 8,478 (53.3) | 3,675 (53.1) | 12,153 (53.2) | 101 (50.5) | ||
| Single | 3,331 (20.9) | 1,410 (20.4) | 4,813 (21.1) | 46 (23.0) | ||
| Othersb | 4,108 (25.8) | 1,840 (26.5) | 5,876 (25.7) | 53 (26.5) | ||
| Grade | 0.46 | 0.33 | ||||
| I | 905 (5.7) | 375 (5.4) | 1,280 (5.6) | 6 (3.0) | ||
| II | 5,571 (35.0) | 2445 (35.3) | 8,016 (35.1) | 76 (38.0) | ||
| III | 9,367 (58.8) | 4,071 (58.8) | 13,438 (58.8) | 118 (59.0) | ||
| IV | 74 (0.5) | 34 (0.5) | 108 (0.5) | 0 (0.0) | ||
| AJCC T | 0.13 | 0.57 | ||||
| T0-1 | 1,982 (12.5) | 797 (11.6) | 2,779 (12.1) | 27 (13.5) | ||
| T2 | 4,771 (30.0) | 2,128 (30.7) | 6,899 (30.2) | 62 (31.0) | ||
| T3 | 5,991 (37.6) | 2,655 (38.3) | 8,646 (37.9) | 66 (33.0) | ||
| T4 | 3,173 (19.9) | 1,345 (19.4) | 4,518 (19.8) | 45 (22.5) | ||
| AJCC N | 0.71 | 0.28 | ||||
| N0 | 2,367 (14.9) | 1,062 (15.3) | 3,429 (15.0) | 29 (14.5) | ||
| N1 | 3,975 (25.0) | 1,733 (25.0) | 5,708 (25.0) | 43 (21.5) | ||
| N2 | 6,358 (39.9) | 2,767 (40.0) | 9,125 (39.9) | 93 (46.5) | ||
| N3 | 3,217 (20.2) | 1,363 (19.7) | 4,580 (20.1) | 35 (17.5) | ||
| Subtype | 0.33 | 0.83 | ||||
| Luminal A | 8,810 (55.3) | 3,856 (55.6) | 12,666 (55.4) | 115 (57.5) | ||
| Luminal B | 2,606 (16.4) | 1,129 (16.3) | 3,735 (16.4) | 32 (16.0) | ||
| Her-2 | 1,575 (9.9) | 634 (9.2) | 2,209 (9.7) | 16 (8.0) | ||
| Triple-negative | 2,926 (18.4) | 1,306 (18.9) | 4,232 (18.5) | 37 (18.5) | ||
| Surgery | 0.23 | <0.01 | ||||
| BCS | 3,519 (22.1) | 1,602 (23.1) | 5,121 (22.4) | 67 (33.5) | ||
| Mastectomy | 11,100 (69.7) | 4,761 (68.8) | 15,861 (69.5) | 123 (61.5) | ||
| No surgery | 1,298 (8.2) | 562 (8.1) | 1,860 (8.1) | 10 (5.0) | ||
| Radiation | 0.08 | 0.41 | ||||
| Yes | 9,343 (58.7) | 4,185 (60.4) | 13,528 (59.2) | 112 (56.0) | ||
| No/Unknown | 6,531 (41.3) | 2,779 (39.6) | 9,314 (40.8) | 88 (44.0) | ||
| Chemotherapy | 0.65 | 0.33 | ||||
| Yes | 12,848 (80.7) | 5,572 (80.5) | 18,420 (80.6) | 156 (78.0) | ||
| No/Unknown | 3,069 (19.3) | 1,353 (19.5) | 4,422 (19.4) | 44 (22.0) |
BCS, breast-conserving surgery; HR, hazard ratio; 95 CI, 95% confidence interval; Othersa, including Asian or Pacific Islander and American Indian/Alaska Native; Othersb, including separated, divorced and widowed; T, Training cohort; IV, Internal validation cohort; EV, External validation cohort.