Table 1.
The demographic, pathological and treatment information of MBC patients diagnosed at 2010–2016 in the SEER database
| Characteristics | The initial cohort | The training cohort | The validating cohort | p value | |||
|---|---|---|---|---|---|---|---|
| Number | Percent (%) | Number | Percent (%) | Number | Percent (%) | ||
| Age | 0.873 | ||||||
| <=40 | 824 | 10.3 | 556 | 10.4 | 268 | 10.1 | |
| <=60 | 3462 | 43.4 | 2305 | 43.3 | 1157 | 43.5 | |
| > 60 | 3700 | 46.3 | 2463 | 46.3 | 1237 | 46.5 | |
| Race | 0.160 | ||||||
| White | 5999 | 75.1 | 4016 | 75.4 | 1983 | 74.5 | |
| Black | 1339 | 16.8 | 898 | 16.9 | 441 | 16.6 | |
| Othersa | 648 | 8.1 | 410 | 7.7 | 238 | 8.9 | |
| Marital status | 0.837 | ||||||
| Unmarriedb | 4208 | 52.7 | 2801 | 52.6 | 1407 | 52.9 | |
| Married | 3778 | 47.3 | 2523 | 47.4 | 1255 | 47.1 | |
| Histology | 0.615 | ||||||
| IDC | 6845 | 85.7 | 4571 | 85.9 | 2274 | 85.4 | |
| ILC | 737 | 9.2 | 480 | 9.0 | 257 | 9.7 | |
| IDC and ILC | 404 | 5.1 | 273 | 5.1 | 131 | 4.9 | |
| Grade | 0.936 | ||||||
| I | 571 | 7.2 | 377 | 7.1 | 194 | 7.3 | |
| II | 3397 | 42.5 | 2269 | 42.6 | 1128 | 42.4 | |
| III/IV | 4018 | 50.3 | 2678 | 50.3 | 1340 | 50.3 | |
| Subtype | 0.431 | ||||||
| HR+/HER2- | 4602 | 57.6 | 3073 | 57.7 | 1529 | 57.4 | |
| HR−/HER2+ | 782 | 9.8 | 504 | 9.5 | 278 | 10.4 | |
| HR+/HER2+ | 1518 | 19.0 | 1009 | 19.0 | 509 | 19.1 | |
| HR−/HER2- | 1084 | 13.6 | 738 | 13.9 | 346 | 13.0 | |
| T stage | 0.524 | ||||||
| T1 | 922 | 11.5 | 616 | 11.6 | 306 | 11.5 | |
| T2 | 2829 | 35.4 | 1857 | 34.9 | 972 | 36.5 | |
| T3 | 1514 | 19.0 | 1015 | 19.1 | 499 | 18.7 | |
| T4 | 2721 | 34.1 | 1836 | 34.5 | 885 | 33.2 | |
| N stage | 0.335 | ||||||
| N0 | 1740 | 21.8 | 1159 | 21.8 | 581 | 21.8 | |
| N1 | 3856 | 48.3 | 2538 | 47.7 | 1318 | 49.5 | |
| N2 | 1093 | 13.7 | 743 | 14.0 | 350 | 13.1 | |
| N3 | 1297 | 16.2 | 884 | 16.6 | 413 | 15.5 | |
| Bone metastasis | 0.420 | ||||||
| no | 2121 | 26.6 | 1399 | 26.3 | 722 | 27.1 | |
| yes | 5865 | 73.4 | 3925 | 73.7 | 1940 | 72.9 | |
| Brain metastasis | 0.661 | ||||||
| no | 7438 | 93.1 | 4954 | 93.1 | 2484 | 93.3 | |
| yes | 548 | 6.9 | 370 | 6.9 | 178 | 6.7 | |
| Liver metastasis | 0.716 | ||||||
| no | 5616 | 70.3 | 3737 | 70.2 | 1879 | 70.6 | |
| yes | 2370 | 29.7 | 1587 | 29.8 | 783 | 29.4 | |
| Lung metastasis | 0.907 | ||||||
| no | 5231 | 65.5 | 3485 | 65.5 | 1746 | 65.6 | |
| yes | 2755 | 34.5 | 1839 | 34.5 | 916 | 34.4 | |
| Surgery | 0.661 | ||||||
| No | 5790 | 72.5 | 3843 | 72.2 | 1947 | 73.1 | |
| BCS | 832 | 10.4 | 560 | 10.5 | 272 | 10.2 | |
| Mastectomy | 1364 | 17.1 | 921 | 17.3 | 443 | 16.6 | |
| Radiotherapy | 0.445 | ||||||
| No/Unknown | 5189 | 65.0 | 3444 | 64.7 | 1745 | 65.6 | |
| Yes | 2797 | 35.0 | 1880 | 35.3 | 917 | 34.4 | |
| Chemotherapy | 0.948 | ||||||
| No/Unknown | 3049 | 38.2 | 2034 | 38.2 | 1015 | 38.1 | |
| Yes | 4937 | 61.8 | 3290 | 61.8 | 1647 | 61.9 | |
aOther races included American Indian/Alaska Native, Asian or Pacific Islander
bUnmarried included divorced, separated, widowed, single (never married) or domestic partner