Management of BI-RADS Category C (Category 3) Mammogram
A BI-RADS Category 3 mammogram requires short-interval follow-up imaging rather than immediate biopsy, with unilateral diagnostic mammography at 6 months, followed by imaging every 6-12 months for 1-2 years total. 1, 2
Understanding BI-RADS Category 3
BI-RADS Category 3 represents "probably benign findings" with a malignancy risk of less than 2%. 1, 2 These findings have high confidence in benignity but not absolute certainty, which is why surveillance rather than immediate biopsy is appropriate. 3
Typical Category 3 lesions include:
- Non-calcified circumscribed solid masses less than 2 cm without suspicious characteristics 3
- Focal asymmetries that are not palpable and lack malignant features 3
- Rounded punctate calcifications in small groups 3
Standard Follow-Up Protocol
Initial 6-month follow-up:
12-month follow-up:
- For women aged 40 years or older: bilateral mammography to ensure the contralateral breast receives appropriate annual screening 1, 4
- For women under 40: continue unilateral imaging of the affected breast 4
Subsequent follow-up:
- Continue imaging every 6-12 months depending on level of concern 1, 4
- Total surveillance period: 1-2 years 1, 2
If stable or resolved: Resume routine annual screening mammography 1, 4
If changes occur: Proceed immediately to tissue biopsy if the lesion increases in size or benign characteristics change 1, 4
Exceptions: When to Proceed Directly to Biopsy
Skip surveillance and perform immediate biopsy with histologic sampling in these specific situations: 1, 4
- Uncertain follow-up compliance: Patient unlikely to return for scheduled surveillance 1, 3
- High patient anxiety: Patient experiences significant distress about waiting 1, 3
- Strong family history of breast cancer: Particularly with genetic predisposition or other high-risk factors 1, 3
- Patient preference: When the patient strongly desires definitive diagnosis 4
Critical Management Pitfalls to Avoid
Do not confuse Category 3 with Category 0: Category 0 ("incomplete assessment") requires additional diagnostic imaging immediately—not surveillance. 1, 2 Category 0 must be completed with diagnostic workup and reclassified into a definitive category before any management decision. 2
Ensure pathology-imaging concordance: If biopsy is performed (either initially or during follow-up), verify that pathology results match imaging expectations. 2, 3 Discordant results mandate repeat imaging and/or additional tissue sampling through surgical excision. 3
Monitor compliance carefully: Approximately 90.9% of Category 3 assessments appropriately receive short-interval follow-up recommendations in current practice, but this varies by radiologist experience and practice setting. 5 Academic centers show higher compliance with proper recommendations. 5
Evidence Supporting Surveillance Over Immediate Biopsy
Research demonstrates that return to routine screening for properly classified BI-RADS 3 lesions results in excellent outcomes with no cancers detected in the quadrant of the lesion during 2-year follow-up (0%; 95% CI, 0.0-0.9%). 6 Recommending short-term follow-up instead of routine screening would increase recall rates from 3.8% to 21.3% without improving cancer detection. 6
The malignancy rate for Category 3 lesions remains consistently below 2% when proper BI-RADS criteria are applied, supporting the surveillance approach over immediate biopsy for appropriately selected lesions. 1, 3