Contrast Enhanced Mammography in Breast Cancer Surveillance

Abstract Purpose: Women with a personal history of breast cancer or DCIS (PHBC) are at increased risk of either a local recurrence or a new primary breast cancer. Adjunctive screening ultrasound or MRI is often used to supplement mammography. Contrast enhanced mammography (CEM) is reported to have higher sensitivity than MG and ultrasound, and similar performance with better accessibility than MRI. Methods: We introduced CEM as a routine single imaging modality for surveillance of those with PHBC. This report is of the first surveillance round outcomes comparing CEM with digital mammography. Results: 73/1191 (6.1%) patients were recalled for further assessment. 35 (48%) were true positives (TP), with 26 invasive cancers and 9 cases of DCIS, while 38 (52%) were false positive (FP) with a positive predictive value (PPV) 47.9%. 32/73 were recalled due to findings on MG, while 41/73 were only recalled due to Contrast. 14/73 had ‘minimal signs’ with a lesion identifiable with knowledge of the Contrast finding while 27/73 were ‘contrast only’. 41% (17/41) of those recalled due to contrast were TP. Contrast-only TPs were found in those with low and high mammographic density (MD). Bilateral screening breast US reduced by 55% in the year after routine surveillance CEM was implemented. Conclusion: Compared to MG, CEM as a single surveillance modality for those with PHBC has higher sensitivity and comparable specificity, identifying additional malignant lesions that appear to be clinically significant. Further investigation of interval cancer and subsequent round cancer detection rates is warranted.