Table 1.
Exam-level characteristics of study participants, overall and by breast cancer status within 1 year follow-up.
| All Screening Examinations | No Breast Cancer | Breast Cancer | ||||
|---|---|---|---|---|---|---|
| N | % | N | % | N | % | |
| Screening mammograms† | 2,512,577 | 100% | 2,500,446 | 100% | 12,131 | 100% |
| Age, years | ||||||
| 40–49 | 623,156 | 25% | 621,093 | 25% | 2,063 | 17% |
| 50–59 | 889,719 | 35% | 885,928 | 35% | 3,791 | 31% |
| 60–69 | 758,883 | 30% | 754,349 | 30% | 4,534 | 37% |
| 70–79 | 240,819 | 10% | 239,076 | 10% | 1,743 | 14% |
| Race/ethnicity | ||||||
| White, non-Hispanic | 1,685,099 | 67% | 1,676,540 | 67% | 8,559 | 71% |
| Black, non-Hispanic | 244,665 | 10% | 243,498 | 10% | 1,167 | 10% |
| Asian/Native Hawaiian/Pacific Islander | 299,151 | 12% | 297,759 | 12% | 1,392 | 11% |
| Hispanic | 134,438 | 5% | 133,990 | 5% | 448 | 4% |
| Other/Mixed/Unknown | 149,224 | 6% | 148,659 | 6% | 565 | 5% |
| Menopausal status | ||||||
| Pre- or peri-menopausal | 651,230 | 29% | 648,736 | 29% | 2,494 | 23% |
| Postmenopausal | 1,440,724 | 65% | 1,432,642 | 65% | 8,082 | 73% |
| Surgical menopausal | 118,989 | 5% | 118,490 | 5% | 499 | 5% |
| Unknown | 301,634 | (12%) | 300,578 | (12%) | 1,056 | (9%) |
| First degree family history of breast cancer | ||||||
| No | 2,009,458 | 83% | 2,000,707 | 83% | 8,751 | 75% |
| Yes | 417,981 | 17% | 415,039 | 17% | 2,942 | 25% |
| Unknown | 85,138 | (3%) | 84,700 | (3%) | 438 | (4%) |
| BI-RADS breast density‡ | ||||||
| Almost entirely fat | 234,897 | 10% | 234,233 | 10% | 664 | 6% |
| Scattered fibroglandular density | 987,913 | 43% | 983,390 | 43% | 4,523 | 41% |
| Heterogeneously dense | 910,134 | 39% | 905,306 | 39% | 4,828 | 44% |
| Extremely dense | 186,699 | 8% | 185,731 | 8% | 968 | 9% |
| Unknown | 192,934 | (8%) | 191,786 | (8%) | 1,148 | (9%) |
| BCSC 5-year risk|| | ||||||
| 0 – <1.00% | 646,582 | 28% | 644,926 | 28% | 1,656 | 15% |
| 1.00–1.66% | 931,062 | 40% | 926,976 | 40% | 4,086 | 37% |
| 1.67–2.49% | 499,586 | 22% | 496,521 | 22% | 3,065 | 28% |
| 2.50–3.99% | 211,302 | 9% | 209,512 | 9% | 1,790 | 16% |
| ≥4.00% | 31,111 | 1% | 30,725 | 1% | 386 | 4% |
| Unknown | 192,934 | (8%) | 191,786 | (8%) | 1,148 | (9%) |
*
Breast cancer cases within 12 months of screening mammography
†
Subsequent screening examinations after first screening mammography and within30 months of prior mammography
‡
Breast Imaging Reporting and Data System (BI-RADS)
||
Breast Cancer Surveillance Consortium (BCSC) 5-year risk calculated using age, race, first degree family history of breast cancer, history of breast biopsy, BI-RADS density.