Atlas of breast cancer early detection

BI-RADS 3 indicates a finding that is most likely benign and not expected to show changes suspicious of malignancy over time. However, it is necessary to ascertain the benign nature through a close follow-up. The findings described in this category have 0–2% risk of malignancy. Only 8% of the patients with a diagnosis of BI-RADS 3 may have a finding suspicious for malignancy on follow-up and require a biopsy.
This category includes:

• non-calcified circumscribed mass on baseline screening mammography, which is likely to be intramammary node, fibroadenoma , cyst or solitary group of calcifications and
• focal asymmetry that does not appear suspicious on spot compression magnification view or another mammographic view and that remains stable on follow-up monitoring.

Surveillance protocols for BI-RADS 3 diagnosis vary across institutions. Repeat examinations are usually performed at 6, 12, and 24 months and a stable finding is diagnosed for BI-RADS 2 .
Detection of a suspicious interval change at follow-up of a BI-RADS 3 lesion changes the category to BI-RADS 4 or 5 and biopsy confirmation is required .