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Clustered Microcysts on Breast Ultrasound: What Is an Appropriate Management Recommendation?
Heather I Greenwood1, Amie Y Lee1, Iryna V Lobach1
11 Department of Radiology and Biomedical Imaging, University of California, San Francisco, Mount Zion Medical Center, 1600 Divisadero St, Rm C-250, San Francisco, CA 94115.
Objective:
The objective of our study was to determine outcomes of lesions identified as clustered microcysts on breast ultrasound to augment the existing literature and help guide appropriate management recommendations.
Materials And Methods:
We retrospectively identified cases at our institution, from January 2003 through December 2013, of all lesions classified as clustered microcysts at breast ultrasound. Breast ultrasound examinations were performed by the interpreting physician. If ultrasound-guided sampling was performed, results were obtained from the pathology or cytology reports. If sampling was not performed, only lesions with at least 24 months of imaging follow-up or any imaging follow-up with interval resolution or decrease in size were included in the study. Outcomes and frequency of malignancy were determined by reviewing the electronic medical records and our PACS.
Results:
Of 144 patients with 148 lesions classified as clustered microcysts on ultrasound, 93 patients with 95 lesions had adequate follow-up and were included in our study population. The mean patient age was 50 years (range, 32-72 years). Of the 16 lesions that underwent percutaneous sampling, none (0% [95% CI, 0-21%]) yielded malignancy. Fourteen (88%) sampled lesions were benign, and two (12%) of the sampled lesions revealed atypical ductal hyperplasia at percutaneous sampling but no atypia or upgrade at subsequent surgical excision. In total, 0 of 95 lesions (0% [95% CI, 0-3.8%]) showed malignancy at sampling or imaging follow-up.
Conclusion:
Our results support that lesions sonographically characterized as clustered microcysts carry an extremely low risk of malignancy, and biopsy should be avoided.
Insights
Clustered microcysts on breast ultrasound have an extremely low risk of malignancy. These findings suggest that routine biopsy for these lesions can be safely avoided, simplifying patient management.
Area of Science:
- Radiology
- Oncology
- Breast Imaging
Background:
- Clustered microcysts are a common finding on breast ultrasound.
- Management recommendations for these lesions are not well-established.
- Further data is needed to guide clinical practice.
Purpose of the Study:
- To determine the outcomes of breast lesions identified as clustered microcysts.
- To assess the malignancy rate of clustered microcysts.
- To inform management strategies for these ultrasound findings.
Main Methods:
- Retrospective review of breast ultrasound cases from 2003-2013.
- Inclusion of lesions with adequate imaging follow-up (≥24 months) or documented resolution.
- Analysis of percutaneous sampling results and imaging follow-up for malignancy.
Main Results:
- 95 lesions in 93 patients met inclusion criteria.
- No malignancies were found in sampled lesions (0%) or overall (0%).
- Two lesions showed atypical ductal hyperplasia on sampling but were benign upon excision.
Conclusions:
- Lesions characterized as clustered microcysts on ultrasound have a very low risk of malignancy.
- Biopsy of these lesions may be unnecessary.
- This supports a less invasive management approach.
