Diagnostic Contrast-Enhanced Mammography Performed Immediately Prior to Same-Day Biopsy: An Analysis of Index Lesion Enhancement Compared to Histopathology and Follow-up in Patients With Suspicious Ultrasound Findings

Abstract

Objective: To measure the diagnostic performance of contrast-enhanced mammography (CEM) for the index lesion when it is performed the same day prior to biopsy in patients with suspicious findings at US.

Methods: This IRB-approved retrospective study compared radiologist original reports of the presence or absence of index lesion enhancement on CEM to biopsy results and follow-up. The most suspicious lesion or the larger of equally suspicious lesions recommended for biopsy by US after a diagnostic workup including mammography was considered the index lesion. CEM exams were performed the same day, immediately prior to the scheduled biopsy, as requested by the radiologist recommending the biopsy. Numeric variables were summarized with means and standard deviations, or medians and the minimum and maximum, where appropriate.

Results: Biopsy demonstrated cancer in 64.7% (200/309) of index lesions. Of these, 197/200 demonstrated enhancement for a sensitivity of 98.5% (95% CI: 95.7%-99.7%) (197/200) and the negative predictive value of CEM for non-enhancing index lesions was 95.1% (58/61; 95% CI: 86.1%-98.4%). The three false negative exams were two grade 1 ER+ HER2- invasive ductal cancers that were 6 mm and 7 mm in size, and a 3-mm grade 2 ductal carcinoma in situ in a complex cystic and solid mass. False positive exams made up 20.6% (51/248) of the positive exams.

Conclusion: Diagnostic CEM showed high sensitivity and specificity for cancer in lesions with suspicious US findings. CEM may reduce the need for some biopsies, and negative CEM may support a true negative biopsy result.

Keywords: biopsy; breast cancer; contrast-enhanced; mammography; ultrasound.

Figure 1.

False-negative contrast-enhanced mammogram (CEM) in a 59-year-old patient who was treated seven years prior for breast cancer with lumpectomy and radiation therapy. Screening mammography tomosynthesis right craniocaudal view (A) shows a subtle mass that had developed at the 12:00 position (circle) for which additional diagnostic imaging was recommended. Diagnostic US (B) confirmed the presence of an appropriately sized and located solid suspicious mass (arrow). Right craniocaudal view from CEM (C) obtained immediately prior to biopsy did not show abnormal enhancement at the site of the mass. US-guided core-needle biopsy (D) of the mass (arrow) was performed. Post-biopsy US (E) and mammogram (F) demonstrates the biopsy marker within the mass (arrow and circle, respectively), which was a 6-mm grade 1 ER+ HER2− infiltrating ductal cancer.