Table 1.
Clinical and pathological characteristics of different cohorts.
| Variable | SEER Cohort | External Validation Cohort | ||||||
|---|---|---|---|---|---|---|---|---|
| Non-LNM | LNM | p | Non-LNM | LNM | p | |||
| N=1405 (%) | n=687 (%) | n=718 (%) | N=142 (%) | n=47 (%) | n=95 (%) | |||
| Age | 62 [52, 71] | 64 [55, 73] | 59 [49, 69] | <0.001 | 52.69 (10.22) | 56.13 (9.69) | 50.99 (10.10) | 0.004 |
| Sex | 0.027 | NA | ||||||
| female | 1378 (98.1) | 680 (99.0) | 698 (97.2) | 142 (100.0) | 47 (100.0) | 95 (100.0) | ||
| male | 27 (1.9) | 7 (1.0) | 20 (2.8) | NA | NA | NA | ||
| Laterality | 0.905 | 0.332 | ||||||
| left | 690 (49.1) | 339 (49.3) | 351 (48.9) | 81 (57.0) | 30 (63.8) | 51 (53.7) | ||
| right | 715 (50.9) | 348 (50.7) | 367 (51.1) | 61 (43.0) | 17 (36.2) | 44 (46.3) | ||
| Subtype | 0.134 | 0.888 | ||||||
| luminal A | 1042 (74.2) | 526 (76.6) | 516 (71.9) | 51 (35.9) | 16 (34.0) | 35 (36.8) | ||
| luminal B | 242 (17.2) | 111 (16.2) | 131 (18.2) | 91 (64.1) | 31 (66.0) | 60 (63.2) | ||
| HER-2 OE | 64 (4.6) | 29 (4.2) | 35 (4.9) | NA | NA | NA | ||
| TNBC | 57 (4.1) | 21 (3.1) | 36 (5.0) | NA | NA | NA | ||
| ER | 0.061 | 1 | ||||||
| negative | 128 (9.1) | 52 (7.6) | 76 (10.6) | 3 (2.1) | 1 (2.1) | 2 (2.1) | ||
| positive | 1277 (90.9) | 635 (92.4) | 642 (89.4) | 139 (97.9) | 46 (97.9) | 93 (97.9) | ||
| PR | 0.837 | 0.426 | ||||||
| negative | 274 (19.5) | 136 (19.8) | 138 (19.2) | 17 (12.0) | 4 (8.5) | 13 (13.7) | ||
| positive | 1131 (80.5) | 551 (80.2) | 580 (80.8) | 125 (88.0) | 43 (91.5) | 82 (86.3) | ||
| HER-2 | 0.238 | 0.951 | ||||||
| negative | 1099 (78.2) | 547 (79.6) | 552 (76.9) | 122 (85.9) | 41 (87.2) | 81 (85.3) | ||
| positive | 306 (21.8) | 140 (20.4) | 166 (23.1) | 20 (14.1) | 6 (12.8) | 14 (14.7) | ||
| Tumor Size | <0.001 | 0.003 | ||||||
| <=20 mm | 793 (56.4) | 532 (77.4) | 261 (36.4) | 73 (51.4) | 33 (70.2) | 40 (42.1) | ||
| 20-50 mm | 469 (33.4) | 142 (20.7) | 327 (45.5) | 67 (47.2) | 14 (29.8) | 53 (55.8) | ||
| >50 mm | 143 (10.2) | 13 (1.9) | 130 (18.1) | 2 (1.4) | 0 (0.0) | 2 (2.1) | ||
LNM, lymph node metastasis; HER2, human epidermal growth factor receptor2; TNBC, triple negative breast cancer; ER, estrogen receptor; PR, progesterone receptor. The bold values/numbers mean: p value < 0.05. NA, Not Available.