Table 1.
Characteristics of patients obtaining diagnostic mammography for evaluation of a breast problem
| 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.