Follow-up of probably benign lesions in non-screening breast diagnostics

Purpose: Our study addresses at the benefit of surveillance of probably benign lesions, detected outside mammographic screening, during a 3-year period. Methods: 28,588 women (mean age 57 ± 12 years) were examined. Two independent radiologists read the mammogram as well as the supplemented ultrasound (in case of breast density ACR type 3 and 4). In the case of discordance a third expert considered whether further examination was indicated or not. Results: 3,266 diagnostic procedures ended with BI-RADS 3 result and 2,512 (76.9 %) women underwent a follow-up examination. 295 (11.7 %) of them received assessment examination (imaging and/or biopsy) and 37 (12.5 %) (none of them palpable) ended with BI-RADS 6. This equals a tumor detection rate of 14.7/1,000. The ratio in situ:invasive was 7:10 (1:1.43) and the mean size was 11.1 ± 4.51 mm. In the total cohort, 536 carcinomas ended with BI-RADS 6 of them 17 % were in situ and 83 % were invasive breast cancers (ratio in situ:invasive 1:4.99), mean size was 13.8 ± 6.3 mm. The cancer detection ratio in these cases was 18.7/1,000. Conclusions: The amount of detected tumors at follow-up of women with preceding BI-RADS 3 equates the associated potential of malignancy.