Table 1 Baseline characteristics of women with primary breast cancer as the first (BCa-1) and second (BCa-2) malignancy: a SEER population-based study in US, 1990–2015
BCa-1 | BCa-2 | |||
|---|---|---|---|---|
N | % | N | % | |
Total number | 883,881 | – | 36,313 | – |
Year of diagnosis | ||||
1990–1993 | 47,727 | 5.4 | 1806 | 5.0 |
1994–1997 | 62,863 | 7.1 | 2380 | 6.6 |
1998–2001 | 117,368 | 13.3 | 3332 | 9.2 |
2002–2005 | 165,528 | 18.7 | 5250 | 14.5 |
2006–2009 | 185,587 | 21.0 | 7775 | 21.4 |
2010–2015 | 304,808 | 34.5 | 15,770 | 43.4 |
Age at diagnosis (mean ± SD), years | 60.5 ± 14.0 | 68.9 ± 12.4 | ||
Race | ||||
White | 708,820 | 80.2 | 30,929 | 85.2 |
Black | 97,049 | 11.0 | 3086 | 8.5 |
Asian | 68,641 | 7.8 | 2127 | 5.9 |
Other | 9371 | 1.1 | 171 | 0.5 |
Cohabitation status | ||||
Non-cohabitation | 359,775 | 40.7 | 17,217 | 47.4 |
Cohabitation | 484,233 | 54.8 | 17,252 | 47.5 |
Unknown | 39,873 | 4.5 | 1844 | 5.1 |
% of High-school education in the county of residence | ||||
Lowest tertile | 173,646 | 19.6 | 6202 | 17.1 |
Middle tertile | 303,827 | 34.4 | 10,779 | 29.7 |
Highest tertile | 406,408 | 46.0 | 19,332 | 53.2 |
Cost of living adjusted median household income in the county of residence | ||||
Lowest tertile | 54,584 | 6.2 | 1885 | 5.2 |
Middle tertile | 116,136 | 13.1 | 4648 | 12.8 |
Highest tertile | 713,161 | 80.7 | 29,780 | 82.0 |