Table 1.
Baseline characteristics of breast cancer with liver metastases at diagnosis in the SEER database
| Variable | Patients, No. % | |
|---|---|---|
| Total (n = 311,573) | With Liver Metastases (n = 4067) | |
| Age, y | ||
| 18–40 | 21,313 (6.8%) | 494 (12.1%) |
| 41–60 | 137,299 (44.1%) | 1882 (46.3%) |
| 61–80 | 129,497 (41.6%) | 1414 (34.8%) |
| > 80 | 23,464 (7.5%) | 277 (6.8%) |
| Race | ||
| White | 207,400 (66.6%) | 2565 (63.1%) |
| Black | 35,062 (11.3%) | 737 (18.1%) |
| Hispanic | 37,499 (12.0%) | 427 (10.5%) |
| Asian or Pacific Islander | 27,997 (9.0%) | 305 (7.5%) |
| American Indian/Alaska Native | 1757 (0.6%) | 23 (0.6%) |
| Unknown | 1858 (0.6%) | 10 (0.2%) |
| Marital status | ||
| Unmarried a | 123,349 (39.6%) | 2011 (49.4%) |
| Married | 171,728 (55.1%) | 1827 (44.9%) |
| Unknown | 16,496 (5.3%) | 229 (5.6%) |
| Insurance status | ||
| Uninsured b | 5417 (1.7%) | 163 (4.0%) |
| Insured | 300,400 (96.4%) | 3821 (94.0%) |
| Unknown | 5756 (1.8%) | 83 (2.0%) |
| Histology | ||
| Infiltrating duct carcinoma | 234,958 (75.4%) | 2971 (73.1%) |
| Lobular carcinoma | 27,050 (8.7%) | 246 (6.0%) |
| Infiltrating duct and lobular carcinoma | 16,392 (5.3%) | 133 (3.3%) |
| Other types c | 33,173 (10.6%) | 717 (17.6%) |
| Pathological Grade | ||
| I | 66,365 (21.3%) | 144 (3.5%) |
| II | 129,786 (41.6%) | 1147 (28.2%) |
| III/IV | 98,850 (31.7%) | 1939 (47.7%) |
| Unknown | 16,572 (5.3%) | 837 (20.6%) |
| Surgery of primary site | ||
| Yes | 285,989 (91.8%) | 952 (23.4%) |
| No | 22,831 (7.3%) | 3052 (75.0%) |
| Unknown | 2753 (0.9%) | 63 (1.5%) |
| Radiotherapy | ||
| Yes | 162,703 (52.2%) | 1082 (26.6%) |
| No/Unknown | 148,870 (47.8) | 2985 (73.4%) |
| Chemotherapy | ||
| Yes | 130,572 (42.0%) | 2802 (68.9%) |
| No/Unknown | 181,001 (58.1%) | 1265 (31.1%) |
| Extrahepatic metastatic sites to lung, brain and bone, No | ||
| 0 | 298,407 (95.8%) | 1060 (26.1%) |
| 1 | 9408 (3.0%) | 1696 (41.7%) |
| 2 | 2747 (0.9%) | 891 (21.9%) |
| All 3 | 343 (0.1%) | 177 (4.4%) |
| Unknown | 668 (0.2%) | 243 (6.0%) |
| Subtype | ||
| HR+/HER2− | 211,127 (67.8%) | 1612 (39.6%) |
| HR+/HER2+ | 32,962 (10.6%) | 884 (21.7%) |
| HR−/HER2+ | 14,089 (4.5%) | 601 (14.8%) |
| Triple-negative | 33,352 (10.7%) | 544 (13.4%) |
| Unknown | 20,043 (6.4%) | 426 (10.5%) |
Notes: a including divorced, separated, single (never married), and widowed; b including insured, Insured/No specifics Any Medicaid; c including other histology of invasive breast cancer except Infiltrating duct carcinoma, Lobular carcinoma and Infiltrating duct and lobular carcinoma; + denotes positive; − denotes negative; * denotes a statistically significant P-value; HER2 Human epidermal growth factor receptor 2, HR Hormone receptor, OR Odds ratio, CI Confidence interval