October 19, 2020 — American Journal of Roentgenology

Abstract

Background: Targeted ultrasound (US) can be performed to characterize and potentially biopsy areas of enhancement detected oncontrast-enhanced mammography (CEM).

Objective: To determine the utility of targeted US in predicting malignancy of indeterminate or suspicious enhancement on CEM.

Methods: 1000 consecutive CEM examinations with a same-day targeted breast US performed at our institution between October 2013 and May 2018 were retrospectively reviewed. All cases with indeterminate or suspicious enhancement detected on CEM that underwent US evaluation were included. Palpable or symptomatic lesions, those with suspicious findings on low-energy mammographic views or on another imaging modality, and those with less than 1-year follow-up were excluded. Medical records, imaging, and pathology were reviewed. Histopathology and follow-up imaging served as reference standards for biopsied and unbiopsied lesions, respectively. Associations between pathologic diagnosis, presence of an US correlate, and lesion characteristics were assessed with Fisher’s exact, chisquared, and Wilcoxon rank-sum tests.

Results: Of 153 enhancing lesions detected on CEM in 144 patients, 47 (31%) had an US correlate. The frequency of a correlate between CEM and US was significantly higher among enhancing masses (28/43) than non-mass enhancement (19/110) (65% vs 17%, P < 0.001). The likelihood of malignancy was significantly higher among lesions with an US correlate (12/47) than among those without an US correlate (11/106) (26% vs 10%, P =0.03), and among mass lesions (11/43) than among non-mass lesions (12/110) (26% vs 11%, P = 0.04). The positive predictive value (PPV) of US-guided biopsy following CEM-directed US was 32%.

Conclusion: Enhancing CEM-detected lesions with an US correlate are more likely to be malignant and can undergo US-guided biopsy to obviate the need to perform additional breast MRI.

Clinical Impact: CEM-directed US for enhancing lesions is useful given that lesions with an US correlate are more likely to be malignant and can serve as targets for US-guided biopsy in the present absence of a commercially available CEM-biopsy system.

Authors: Kristen Coffey, MD, Janice Sung, MD, Christopher Comstock, MD, Gulce Askin, MPH, Maxine Jochelson, MD, Elizabeth Morris, MD, Donna D’Alessio, MD

doi:10.2214/AJR.20.24368