Table 2.
Number and rate (per 1000 screening examinations) of screen-detected, interval cancer and false-positive screening examinations (per 100 screening examinations) in mammographic screening performed in the US, Norway, and Spain
| US | Norway | Spain | |
|---|---|---|---|
| (1996–2008) n = 2,656,834 n (rate) | (1996–2007) 1,470,854 n (rate) | (1996–2009) 1,585,906 n (rate) | |
| Screen-detected cancers (n, rate per 1000 screening examinations) | |||
| All malignant lesions | 11,916 (4.5 ‰) | 8105 (5.5 ‰) | 6409 (4.0 ‰) |
| Invasive | 9028 (3.4 ‰) | 6714 (4.6 ‰) | 5147 (3.2 ‰) |
| DCIS | 2888 (1.1 ‰) | 1391 (0.9 ‰) | 1077 (0.7 ‰) |
| Unknown | 0 | 0 | 185 (0.1 ‰) |
| Interval cancers (n, rate per 1000 screening examinations) | |||
| All malignancies | 2429 (0.9 ‰) | 2623 (1.8 ‰) | 1704 (1.1 ‰) |
| Invasive | 2191 (0.8 ‰) | 2485 (1.7 ‰) | (NA) |
| DCIS | 238 (0.1 ‰) | 138 (0.1 ‰) | (NA) |
| False-positive screening examinations (n, rate per 100 screening examinations) | |||
| Additional imaging | 230,016 (8.7 %) | 42,426 (2.9 %) | 59,414 (3.7 %) |
| Invasive procedures | 24,627 (0.9 %)a | 12,476 (0.8 %) | 10,229 (0.6 %) |
aUS data do not capture all biopsies: the number of women who were recommended to receive a biopsy, defined as BI-RADS assessment at the end of all imaging workup of 4 or 5, or BI-RADS assessment of 0 or 3 accompanied by recommendation for biopsy, FNAC, or surgical consult is thus reported