From the Guidelines
The next imaging step for a patient with focal asymmetries in the left breast that require additional evaluation after a mammogram review is a diagnostic mammogram with additional views, often accompanied by an ultrasound of the area of concern. This approach is supported by the National Comprehensive Cancer Network (NCCN) guidelines, which recommend a diagnostic mammogram and ultrasound evaluation for women aged 30 years or older with asymmetric thickening or nodularity [ 1 ]. The diagnostic mammogram may include spot compression views to help characterize the asymmetry, while ultrasound can help determine if the asymmetry represents a solid mass, fluid-filled cyst, or normal overlapping breast tissue.
Key considerations in the workup of focal asymmetries include:
- Patient age: For women under 30 years old, ultrasound evaluation is often the initial step, while for women 30 years or older, a diagnostic mammogram and ultrasound are recommended [ 1 ].
- BI-RADS category: If the overall imaging findings are classified as BI-RADS category 1-3, clinical reexamination with imaging as needed in 3 to 6 months is recommended, while category 4 or 5 findings warrant a tissue biopsy [ 1 ].
- Clinical suspicion: If a clinically suspicious change is noted, a tissue biopsy is recommended, regardless of the BI-RADS category [ 1 ].
By following this approach, radiologists can carefully assess focal asymmetries and determine the best course of action to rule out malignancy and ensure optimal patient outcomes.
From the Research
Next Imaging Steps for Focal Asymmetries in the Left Breast
The next imaging steps for a patient with focal asymmetries in the left breast that require additional evaluation after a mammogram review are:
- Diagnostic mammography to fully characterize and localize the asymmetry in three-dimensional space, which may include additional spot compression, lateral, and/or rolled views 2
- Digital breast tomosynthesis to aid in evaluation by improving radiologists' sensitivity and specificity, as well as allowing localization of the lesion 2
- Targeted ultrasonography (US) to identify potentially benign causes of the developing asymmetry or identify a target for biopsy 2
- Diagnostic breast magnetic resonance imaging (MRI) for problem solving or biopsy planning if no US correlate is identified and stereotactic biopsy is not feasible 2
Role of Ultrasonography and MRI
- Ultrasonography can safely exclude malignancy if a benign correlate is found, with a negative predictive value (NPV) of 89% for B3 and B5 lesions and 96% for B5 lesions 3
- MRI-guided biopsy can provide an accurate and safe method for sampling suspicious lesions when no other reasonable means of biopsy is available, yielding clinically significant findings in approximately one-third of the sampled specimens 4
Additional Considerations
- Sonography is a useful tool in distinguishing simple cysts from complicated cysts and complex masses of the breast, and can aid in the diagnostic and therapeutic management of cystic breast lesions 5