Table 2. Characteristics of the study population.
| Total population | UMCU | UMCN | AvL | |
|---|---|---|---|---|
| Number of patients | 718 | 202 | 237 | 279 |
| Number of lesions | 749 | 211 | 255 | 283 |
| Age (range) | 54.7 (21–85) | 52.8 (24–85) | 54.8 (26–84) | 55.9 (21–83) |
| Reason for examination | ||||
| Screen-detected lesions | 208 (27.8) | 56 (26.5) | 90 (35.3) | 62 (21.9) |
| Family history of breast cancer | 98 (13.6) | 27 (13.4) | 49 (20.7) | 22 (7.9) |
| History of breast cancer | 136 (18.9) | 33 (16.3) | 39 (16.5) | 64 (22.9) |
| Other a | 155 (21.6) | 58 (28.7) | 54 (22.8) | 43 (15.4) |
| Unknown | 152 (21.2) | 37 (18.3) | 23 (9.7) | 92 (32.9) |
| Mammography | 729 (97.3) | 208 (98.6) | 245 (96.1) | 276 (97.5) |
| Only microcalcifications | 223 (30.6) | 63 (30.3) | 73 (29.7) | 87 (31.5) |
| Density with microcalcifications | 85 (11.7) | 18 (8.7) | 33 (13.5) | 34 (12.3) |
| Density | 252 (34.5) | 72 (34.6) | 81 (33.1) | 99 (35.9) |
| Spiculated density | 96 (13.2) | 22 (10.5) | 32 (13.1) | 42 (15.3) |
| Focal asymmetry | 3 (0.4) | 1 (0.5) | 2 (0.8) | 0 |
| Architectural distortion | 12 (1.6) | 1 (0.5) | 9 (3.7) | 2 (0.7) |
| Not visible | 56 (7.7) | 31 (14.9) | 15 (6.1) | 10 (3.6) |
| Unknown | 2 (0.3) | 0 | 0 | 2 (0.7) |
| Ultrasonography | ||||
| Number (% of lesion per clinic) | 567 (75.7) | 135 (64.0) | 202 (79.2) | 230 (81.3) |
| Solid | 410 (72.3) | 110 (81.5) | 128 (63.4) | 172 (74.8) |
| Both solid and cystic | 16 (2.8) | 6 (4.4) | 7 (3.5) | 3 (1.3) |
| Not described | 16 (2.8) | 1 (0.7) | 8 (3.9) | 7 (3.0) |
| Not visible | 125 (22.1) | 18 (13.4) | 59 (29.2) | 48 (20.9) |
| Radiologic diameter of lesion | ||||
| No. of cases known (%) | 450 (60.1) | 84 (39.8) | 169 (66.3) | 197 (69.6) |
| mm (s.d.) | 13.9 (10.8) | 10.9 (5.3) | 16.3 (12.7) | 13.0 (10.3) |
| Primary diagnostic intervention | ||||
| Diagnostic surgery | 316 (42.2) | 79 (37.4) | 129 (50.6) | 108 (38.2) |
| FNA ultrasound guided | 242 (32.3) | 72 (34.1) | 0 | 170 (60.1) |
| LCNB ultrasound guided | 128 (17.1) | 21 (10.0) | 102 (40.0) | 5 (1.7) |
| LCNB stereotactic guided | 63 (8.4) | 39 (18.5) | 24 (9.4) | 0 |
| Malignant lesions (histology)b | 378 (50.4) | 84 (39.8) | 130 (50.9) | 164 (57.9) |
| DCIS | 102 (27.0) | 26 (31.0) | 34 (26.2) | 42 (25.6) |
| Invasive carcinoma | 276 (73.0) | 58 (69.0) | 96 (73.8) | 122 (74.4) |
a
Includes: palpable lesion somewhere else in the breast(s), follow-up for benign condition in the past, pain, hormone replacement therapy.
b
Histology report from surgical specimen (‘Gold standard’)