Table 1.
Characteristics of breast cancer patients with distant metastasis from SEER 18 population-based registries by age groups.
| Age < 50 years n = 850 (100%) | 50–69 years n = 2,540 (100%) | Age > 69 years n = 1,542 (100%) | Total n = 4,932(100%) | P-valuea | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| No. | % | No. | % | No. | % | No. | % | |||
| Gender | Female | 841 | 98.9% | 2,512 | 98.9% | 1,519 | 98.5% | 4,872 | 98.8% | 0.491 |
| Male | 9 | 1.1% | 28 | 1.1% | 23 | 1.5% | 60 | 1.2% | ||
| Year of diagnosis | 2010 | 205 | 24.1% | 639 | 25.2% | 357 | 23.2% | 1,201 | 24.4% | 0.432 |
| 2011 | 225 | 26.5% | 624 | 24.6% | 380 | 24.6% | 1,229 | 24.9% | ||
| 2012 | 221 | 26.0% | 634 | 25.0% | 387 | 25.1% | 1,242 | 25.2% | ||
| 2013 | 199 | 23.4% | 643 | 25.3% | 418 | 27.1% | 1,260 | 25.5% | ||
| Race | White | 578 | 68.0% | 1,843 | 72.6% | 1,267 | 82.2% | 3,688 | 74.8% | <0.001 |
| Black | 182 | 21.4% | 472 | 18.6% | 208 | 13.5% | 862 | 17.5% | ||
| Othersb | 87 | 10.2% | 207 | 8.1% | 59 | 3.8% | 353 | 7.2% | ||
| Unknown | 3 | 0.4% | 18 | 0.7% | 8 | 0.5% | 29 | 0.6% | ||
| T stage | T0 | 23 | 2.7% | 144 | 5.7% | 109 | 7.1% | 276 | 5.6% | <0.001 |
| T1 | 63 | 7.4% | 168 | 6.6% | 92 | 6.0% | 323 | 6.5% | ||
| T2 | 157 | 18.5% | 289 | 11.4% | 189 | 12.3% | 635 | 12.9% | ||
| T3 | 108 | 12.7% | 249 | 9.8% | 129 | 8.4% | 486 | 9.9% | ||
| T4 | 326 | 38.4% | 1,001 | 39.4% | 483 | 31.3% | 1,810 | 36.7% | ||
| Tx | 173 | 20.4% | 689 | 27.1% | 540 | 35.0% | 1,402 | 28.4% | ||
| N stage | N0 | 149 | 17.5% | 534 | 21.0% | 418 | 27.1% | 1,101 | 22.3% | <0.001 |
| N1 | 357 | 42.0% | 910 | 35.8% | 481 | 31.2% | 1,748 | 35.4% | ||
| N2 | 91 | 10.7% | 271 | 10.7% | 119 | 7.7% | 481 | 9.8% | ||
| N3 | 152 | 17.9% | 380 | 15.0% | 137 | 8.9% | 669 | 13.6% | ||
| Nx | 101 | 11.9% | 445 | 17.5% | 387 | 25.1% | 933 | 18.9% | ||
| Molecular subtypec | Her2−/HoR+ | 402 | 47.3% | 1,228 | 48.4% | 737 | 47.8% | 2,367 | 48.0% | <0.001 |
| Her2 + /HoR + | 148 | 17.4% | 308 | 12.1% | 130 | 8.4% | 586 | 11.9% | ||
| Her2+/HoR− | 82 | 9.6% | 185 | 7.3% | 72 | 4.7% | 339 | 6.9% | ||
| Triple Negative | 111 | 13.1% | 277 | 10.9% | 143 | 9.3% | 531 | 10.8% | ||
| Unknown | 107 | 12.6% | 541 | 21.3% | 460 | 29.8% | 1,109 | 22.5% | ||
| Surgeryd | No | 542 | 63.8% | 1,910 | 75.2% | 1,273 | 82.6% | 3,725 | 75.5% | <0.001 |
| Yes | 301 | 35.4% | 611 | 12.4% | 259 | 16.8% | 1,171 | 23.7% | ||
| Unknown | 7 | 0.8% | 19 | 0.7% | 10 | 0.6% | 36 | 0.7% | ||
| Radiation | No | 517 | 60.8% | 1,743 | 68.6% | 1,161 | 75.3% | 3,421 | 69.4% | <0.001 |
| Yes | 305 | 35.9% | 728 | 28.7% | 342 | 22.2% | 1,375 | 27.9% | ||
| Unknown | 28 | 3.3% | 69 | 2.7% | 39 | 2.5% | 136 | 2.8% | ||
| Median follow-up (months) | 14 (5–26) | 11 (3–22) | 6 (1–18) | 10 (2–22) | ||||||
aThe bold type indicates statistically significance.
bOther races includes American Indian, AK Native, Asian and Pacific Islander.
cHer2: human epidermal growth factor receptor-2; HoR: hormone receptor.
dThe surgery only included surgery at the primary site.