Scientific Session 28 — Breast - Screening/PathologyFriday, May 5, 2017
2311. Clustered Microcysts on Breast Sonography: What is an Appropriate Management Recommendation?
Greenwood H*, Lee A, Carpentier B, Freimanis R, Strachowski L. University of California San Francisco, San Francisco, CA
Address correspondence to H. Greenwood (email@example.com)
Objective: Our objective was to determine the appropriate clinical management recommendations based upon the outcomes of lesions prospectively identified as clustered microcysts on breast sonography.
Materials and Methods: We retrospectively identified cases at our institution (January 2003–December 2013) of all lesions prospectively classified by the interpreting radiologist as clustered microcysts at breast sonography, in accordance with the American College of Radiology BI-RADS definition. All breast ultrasounds were performed directly by the interpreting physician using either a 15L8w-S or 17L5-HD transducer. If biopsy was performed, the results were obtained from pathology or cytology reports. If biopsy was not performed, only lesions with adequate follow-up, defined as at least 12 months of imaging follow-up or at least 24 months of clinical follow-up, were included in our study population. Outcomes and frequency of malignancy were determined by electronic medical record review and PACS.
Results: Of 144 patients with 148 lesions classified as clustered microcysts, 123 lesions in 120 patients met our inclusion criteria. The mean patient age was 49.9 years (range, 27–76 years).Seventeen lesions underwent biopsy, 106 lesions had at least 12 months of imaging follow-up (mean ± SD, 49.3 ± 28.9 months), and 15 lesions had at least 24 months of clinical follow-up (46.3 ± 21.6 months). Of the 123 included lesions, 73 (59%) were identified from an ultrasound directed to a mammographic finding, 23 (19%) presented as a palpable lump, 22 (18%) were incidentally identified at sonography, 3 (2.4%) presented as focal pain, one (0.8%) was identified as a correlate to an MRI finding, and one (0.8%) was identified during imaging evaluation of nipple discharge. Of the 17 lesions that underwent percutaneous biopsy, none (0%) yielded malignancy. Fifteen (88%) biopsied lesions had benign results; 14 of these yielded benign fibrocystic changes and one had focally dense stroma. Two (12%) of the biopsied lesions revealed atypical ductal hyperplasia at percutaneous biopsy, but demonstrated benign pathology findings at subsequent surgical excision. In total, among all cases of clustered microcysts, zero (0/123) represented cancer at biopsy, imaging, or clinical follow-up.
Conclusion: Clustered microcysts are frequently identified on breast sonography; however, there is a paucity of literature on the outcomes of such lesions, limiting the radiologist’s ability to confidently issue an appropriate assessment and management recommendation. In this largest study on clustered microcysts to date, our results support that when clustered microcysts are identified by breast sonography, the risk of malignancy is extremely low to nonexistent, and biopsy should be avoided.