Table 1.
Patient characteristic* | Total diagnostic mammograms, No. | Diagnostic mammograms | Without cancer, No. (%) | With cancer, No. (%) |
Patient's age, y | ||||
<40 | 5467 | 5351 (20.0) | 116 (8.7) | |
40–49 | 9827 | 9502 (35.5) | 325 (24.5) | |
50–59 | 6201 | 5872 (21.9) | 329 (24.8) | |
60–69 | 3120 | 2923 (10.9) | 197 (14.8) | |
≥70 | 3485 | 3123 (11.7) | 362 (27.2) | |
Mammographic breast density | ||||
Almost entirely fat | 1504 | 1435 (5.4) | 69 (5.2) | |
Scattered fibroglandular densities | 9266 | 8838 (33.0) | 428 (32.2) | |
Heterogeneously dense | 12 582 | 11 935 (44.6) | 647 (48.7) | |
Extremely dense | 4748 | 4563 (17.0) | 185 (13.9) | |
Time since last screening or diagnostic mammogram | ||||
<1 y | 7822 | 7460 (27.9) | 362 (27.2) | |
1 to <3 y | 12 255 | 11 726 (43.8) | 529 (39.8) | |
≥3 y | 3521 | 3290 (12.3) | 231 (17.4) | |
No previous mammography | 4502 | 4295 (16.0) | 207 (15.6) | |
Reported presence of a breast lump | ||||
No | 10 189 | 9943 (37.1) | 246 (18.5) | |
Yes | 17 911 | 16 828 (62.9) | 1083 (81.5) |
Based on main study cohort of 28 100 diagnostic mammograms (26 771 without cancer and 1329 with cancer) from 32 facilities.