What should you know?
BI-RADS is the American College of Radiology system for standardized mammography, ultrasound and breast MRI reporting. The final category communicates the assessment and recommended next step; it is not a cancer stage.
Category 0 is incomplete; 1 is negative; 2 is benign; 3 is probably benign with short-interval follow-up; 4 is suspicious and biopsy is considered; 5 is highly suggestive of malignancy; 6 is known biopsy-proven malignancy.
Common symptoms and signs
- BI-RADS is not a cancer stage
- Read the category together with the recommendation
- Category 3 generally means imaging surveillance
- Category 4 has subcategories and often leads to tissue diagnosis
Diagnosis and the role of ultrasound
The final category is based on standardized features and comparison with prior studies. Different modalities provide complementary information and may receive modality-specific assessments.
- Whether the evaluation is complete
- Routine screening versus short follow-up
- Whether biopsy is recommended
- Correlation with a palpable finding
Treatment and next steps
Follow the written recommendation: complete additional imaging for category 0, routine care for 1–2, scheduled follow-up for 3 and prompt biopsy discussion for 4–5. Category 6 is managed as a confirmed diagnosis.
When is urgent care needed?
- Do not delay follow-up for BI-RADS 4 or 5
- Seek review for a rapidly growing lump despite a prior result
- Promptly assess new nipple retraction, bloody discharge or skin tethering