Next Imaging After Mammogram Shows Possible Mass
Perform targeted breast ultrasound immediately after the diagnostic mammogram, regardless of what the mammogram shows. 1
Algorithmic Approach Based on Mammographic Findings
If Mammogram Shows a Definite Benign Mass (BI-RADS 2)
- When mammography demonstrates a clearly benign mass (lymph node, hamartoma, lipoma, calcified fibroadenoma, or oil cyst) that definitively correlates with any palpable finding, ultrasound is not necessary and clinical follow-up alone is appropriate. 1
- However, if correlation between the mammographic finding and the clinical concern is uncertain, ultrasound is mandatory and should be targeted specifically to the area of concern. 1
If Mammogram Shows a Suspicious or Indeterminate Mass (BI-RADS 3,4, or 5)
- Ultrasound is always the next step to characterize the lesion, identify additional occult lesions, and determine the optimal biopsy approach. 1
- Ultrasound detects 93-100% of cancers that are occult on mammography, and when combined with mammography provides a negative predictive value exceeding 97%. 1, 2
- Ultrasound allows direct correlation between clinical findings and imaging, and permits ultrasound-guided biopsy rather than stereotactic biopsy when a sonographic correlate is identified—this is easier to tolerate, avoids radiation, and allows access to posterior or axillary lesions. 1
If Mammogram is Negative but a Palpable Mass Exists
- Ultrasound is mandatory because mammography has only 86-91% sensitivity for palpable masses, and ultrasound identifies 40% of benign palpable masses that are mammographically occult. 1
- A suspicious physical examination should prompt biopsy regardless of negative imaging, as negative mammography and ultrasound should never override a highly suspicious clinical finding. 1, 2
What NOT to Do
- Do not order MRI, PET, FDG-PEM, or molecular breast imaging as the next step after an abnormal screening mammogram—these modalities have no role in the initial evaluation of a possible mass. 1, 2
- Do not proceed directly to biopsy before completing all imaging, because biopsy-related changes (hematoma, architectural distortion) will confuse, alter, and obscure subsequent image interpretation. 1, 2
- Do not order short-interval follow-up mammography for a suspicious finding—tissue sampling is required, not surveillance. 1
Age-Specific Considerations
- Women ≥40 years: Diagnostic mammography is the first imaging study, followed immediately by targeted ultrasound. 2
- Women 30-39 years: Either diagnostic mammography or ultrasound may be performed first, depending on clinical suspicion. 2
- Women <30 years: Proceed directly to targeted ultrasound as the initial study, reserving mammography only for cases where ultrasound shows suspicious findings or clinical examination is highly concerning. 2
Critical Pitfall
The most common error is assuming a palpable mass is benign simply because mammography is negative. 3 Ultrasound must always be performed to complete the diagnostic evaluation, and any highly suspicious palpable mass requires biopsy even when both mammography and ultrasound appear benign. 1, 2