Table 1 Demographic and clinical characteristics by body mass index (BMI) subgroups
Total N = 2084 | Underweight BMI < 18.50 N = 71 | Normal 18.5 ≤ BMI < 24 N = 1045 | Overweight BMI ≥ 24 N = 968 | p value | |
|---|---|---|---|---|---|
Age, years | 53.4 ± 11.2 | 47.6 ± 11.6 | 51.4 ± 10.7 | 56.1 ± 11.1 | < 0.01†|
Location | 0.36 | ||||
 Right | 1006 (48.3) | 38 (53.5) | 515 (49.3) | 453 (46.8) | |
 Left | 1078 (51.7) | 33 (46.5) | 530 (50.7) | 515 (53.2) | |
Tumor size on MRI, cm | 3.4 ± 1.9 | 3.0 ± 1.6 | 3.2 ± 1.8 | 3.6 ± 1.9 | < 0.01†|
Surgical method | 0.52 | ||||
 Total mastectomy | 928 (44.5) | 34 (47.9) | 475 (45.5) | 419 (43.3) | |
 Partial mastectomy (BCS) | 1156 (55.5) | 37 (52.1) | 570 (54.5) | 549 (56.7) | |
Specimen size, gm | |||||
 Total mastectomy | 346.5 ± 200.1 | 153.7 ± 97.6 | 280.8 ± 140.8 | 466.9 ± 221.7 | < 0.01†|
 Partial mastectomy (BCS) | 62.7 ± 59.4 | 35 ± 22.8 | 53.1 ± 53.2 | 76.6 ± 65.6 | < 0.01†|
Surgical ALN staging method | < 0.01†| ||||
 SLNB | 405 (19.4) | 11 (15.5) | 182 (17.4) | 212 (21.9) | |
 SLNB + ALND | 1392 (66.8) | 54 (76.1) | 736 (70.4) | 602 (62.2) | |
 ALND | 287 (13.8) | 6 (8.5) | 127 (12.2) | 154 (15.9) | |
Pathologic tumor size, cm | 2.3 ± 1.6 | 2.0 ± 1.5 | 2.2 ± 1.6 | 2.4 ± 1.6 | < 0.01†|
Pathologic stage | < 0.01†| ||||
 I | 856 (41.1) | 37 (52.1) | 485 (46.4) | 334 (34.5) | |
 II | 1000 (48.0) | 25 (35.2) | 464 (44.4) | 511 (52.8) | |
 III | 220 (10.6) | 9 (12.7) | 92 (8.8) | 119 (12.3) | |
 IV | 8 (0.4) | 0 | 4 (0.4) | 4 (0.4) | |
Histological type | N/A = 63 | 0.73 | |||
 IDC | 1822 (90.2) | 65 (91.5) | 921 (90.6) | 836 (89.5) | |
 ILC | 97 (4.8) | 3 (4.2) | 50 (4.9) | 44 (4.7) | |
 Othersa | 102 (5.0) | 3 (4.2) | 45 (4.4) | 54 (5.8) | |
Grade | N/A = 42 | 0.50 | |||
 I | 420 (20.6) | 16 (23.2) | 223 (21.7) | 181 (19.1) | |
 II | 1137 (55.7) | 34 (49.3) | 562 (54.7) | 541 (57.2) | |
 III | 485 (23.8) | 19 (27.5) | 242 (23.6) | 224 (23.7) | |
ER | N/A = 10 | 0.71 | |||
 Positive | 1714 (82.6) | 61 (85.9) | 856 (82.2) | 797 (82.8) | |
 Negative | 360 (17.4) | 10 (14.1) | 185 (17.8) | 165 (17.2) | |
PR | N/A = 9 | 0.77 | |||
 Positive | 1533 (73.9) | 55 (77.5) | 767 (73.6) | 711 (73.9) | |
 Negative | 542 (26.1) | 16 (22.5) | 275 (26.4) | 251 (26.1) | |
HER-2 | N/A = 26 | 0.63 | |||
 Positive | 403 (19.6) | 17 (23.9) | 199 (19.3) | 187 (19.6) | |
 Negative | 1655 (80.4) | 54 (76.1) | 832 (80.7) | 769 (80.4) | |
Ki 67 | N/A = 178 | 0.22 | |||
 ≦ 14 | 779 (40.9) | 33 (48.5) | 398 (41.9) | 348 (39.2) | |
 > 14 | 1127 (59.1) | 35 (51.5) | 553 (58.1) | 539 (60.8) | |
Molecular subtype | N/A = 75 | ||||
 Luminal A | 767 (38.2) | 26 (39.4) | 401 (39.9) | 340 (36.2) | 0.61 |
 Luminal B1 | 658 (32.8) | 23 (34.8) | 314 (31.2) | 321 (34.2) | |
 Luminal B2 | 266 (13.2) | 9 (13.6) | 128 (12.7) | 129 (13.8) | |
 HER-2(+) | 151 (7.5) | 6 (9.1) | 78 (7.8) | 67 (7.1) | |
 TNBC | 167 (8.3) | 2 (3.0) | 84 (8.4) | 81 (8.6) | |