Concordance Framework
Concordant Benign — Imaging and pathology both benign → routine follow-up per BI-RADS recommendation. Confirm marker clip position on post-biopsy imaging.
Concordant Malignant — Imaging suspicious/malignant AND pathology shows malignancy → proceed with treatment planning (surgical oncology referral, staging workup).
Discordant — Benign path after suspicious imaging — Imaging is BI-RADS 4B, 4C, or 5 but pathology shows a benign finding → repeat core needle biopsy or surgical excision required. This is the most dangerous discordance scenario — the probability of malignancy implied by the BI-RADS category is not explained by the pathology.
Discordant — High-risk path after low-suspicion imaging — Imaging appears benign/low suspicion but pathology shows a high-risk lesion (ADH, LCIS, papilloma with atypia) → excision typically required. May represent undersampling.
BI-RADS 4C or 5 + benign pathology = discordant. A benign result after a highly suspicious image is almost never truly concordant — it implies either sampling error or a missed adjacent lesion. Repeat biopsy or surgical excision is the appropriate response.
Common Concordant Benign Pairs
| Imaging Finding | Pathology Result | Status | Follow-up |
|---|---|---|---|
| Oval circumscribed mass, BI-RADS 3 or 4A | Fibroadenoma | Concordant | 6-month follow-up or return to annual per clinical context |
| Oval circumscribed mass, BI-RADS 3 | Fibrocystic changes | Concordant | Continue BI-RADS 3 surveillance (6 mo → 12 mo → 24 mo) |
| Grouped amorphous calcifications, BI-RADS 4A | Fibrocystic change ± sclerosing adenosis | Concordant | 6-month follow-up mammogram with magnification views |
| Simple cyst on US | Benign cyst contents on aspiration | Concordant | Routine; re-image only if symptomatic recurrence |
| Oval circumscribed mass on MRI | Fibroadenoma with dark septations | Concordant | Routine; correlate with mammography/US |
Discordant Examples — Action Required
| Imaging Finding | Pathology Result | Status | Required Action |
|---|---|---|---|
| Spiculated mass, BI-RADS 5 | Fibrocystic change — benign | Discordant | Repeat CNB or immediate surgical excision — BI-RADS 5 requires ≥95% probability; benign path is insufficient |
| Irregular mass with rim enhancement, BI-RADS 4C (MRI) | Benign fibroadenoma | Discordant | Repeat biopsy — fibroadenoma does not cause rim enhancement; sampling error likely |
| Fine linear branching calcifications, BI-RADS 4C | ADH (not DCIS) | Discordant | Surgical excision — fine linear calcs strongly suggest DCIS; ADH on core = likely undersampling of DCIS |
| Segmental NME on MRI, BI-RADS 4B | Usual ductal hyperplasia only | Discordant | Surgical excision — segmental NME with UDH alone is discordant; DCIS must be excluded |
| BI-RADS 4A mass | Phyllodes tumor (borderline) | Discordant | Surgical excision with clear margins — phyllodes at any grade requires excision; core cannot assess stromal overgrowth |
Post-Biopsy Documentation
- Marker clip: Confirm clip deployment and position on post-biopsy imaging (mammogram or US). Document position relative to biopsy cavity.
- Clip migration: If clip migrates >1 cm from target, document and consider additional bracketing clip placement.
- Post-biopsy hematoma: Correlate with imaging target at 6-month follow-up to confirm clip is within or adjacent to the index lesion.
- Post-biopsy mammogram: Required after stereotactic or tomosynthesis-guided biopsy to confirm clip placement and calcium removal (for calcification biopsies).