Table 2. Clinical characteristics of patients with only BC (BC group) and those with BC followed by TC (BC2TC group).
| Variable | BC (n = 629,976) | BC2TC (n = 1,262) | chi-square P-value |
|---|---|---|---|
| Race | P< 0.001 | ||
| White | 506,105 (80.3%) | 1,010 (80.0%) | |
| Black | 67,537 (10.7%) | 102 (8.1%) | |
| Other | 51,708 (8.2%) | 145 (11.5%) | |
| Unknown | 4,626 (0.7%) | 5 (0.4%) | |
| TNM Stage | P< 0.001 | ||
| IV | 32,393 (5.1%) | 18 (1.4%) | |
| III | 77,388 (12.3%) | 172 (13.6%) | |
| II | 209,060 (33.2%) | 451 (35.7%) | |
| I | 274,310 (43.5%) | 561 (44.5%) | |
| Grade | p = 0.044 | ||
| IV | 6,765 (1.1%) | 23 (1.8%) | |
| III | 203,557 (32.3%) | 428 (33.9%) | |
| II | 241,996 (38.4%) | 494 (39.1%) | |
| I | 121,126 (19.2%) | 227 (18.0%) | |
| ER-positive | p = 0.234 | ||
| No | 115,782 (18.4%) | 213 (16.9%) | |
| Yes | 455,785 (72.3%) | 918 (72.7%) | |
| PR-positive | p = 0.539 | ||
| No | 177,243 (28.1%) | 340 (26.9%) | |
| Yes | 386,656 (61.4%) | 772 (61.2%) | |
| Her-2-positive | p = 0.062 | ||
| No | 180,368 (28.6%) | 189 (15.0%) | |
| Yes | 33,890 (5.4%) | 48 (3.8%) | |
| Breast histology | p = 0.036 | ||
| Infiltrating ductal carcinoma | 452,423 (71.8%) | 898 (71.2%) | |
| Infiltrating lobular carcinoma | 50,069 (7.9%) | 79 (6.3%) | |
| Mixed invasive | 60,781 (9.6%) | 146 (11.6%) | |
| Inflammatory | 3,953 (0.6%) | 6 (0.5%) | |
| Other | 62,750 (10.0%) | 133 (10.5%) | |
| Radiation therapy | p = 0.033 | ||
| Yes | 307,043 (48.7%) | 653 (51.7%) | |
| No/Unknown | 322,933 (51.3%) | 609 (48.3%) | |
| Chemotherapy | P< 0.001 | ||
| Yes | 260,797 (41.4%) | 637 (50.5%) | |
| No/Unknown | 369,180 (58.6%) | 625 (49.5%) |