Clinical Performance of Contrast-Enhanced Mammography Versus Breast MRI in Women at Increased Breast Cancer Risk

TL;DR

Contrast-enhanced mammography (CEM) performs as well as breast MRI in detecting breast cancer in high-risk women, offering a practical and accessible alternative.

Contribution

This study demonstrates that CEM is noninferior to breast MRI and superior to standard mammography in detecting breast cancer in high-risk women.

Findings

CEM detected more cancers than low-energy mammography and performed as well as breast MRI.

CEM had a higher sensitivity and similar specificity compared to low-energy mammography.

CEM maintained a safe radiation dose while achieving diagnostic accuracy comparable to MRI.

Abstract

Women at increased risk for breast cancer need highly sensitive imaging to detect tumors early. Breast MRI is effective but can be costly, time-consuming, or unavailable in some settings. Contrast-enhanced mammography (CEM) is a newer imaging method that combines standard mammography with a safe contrast agent to highlight areas of abnormal blood flow in the breast. In this study, we compared CEM with low-energy CEM (used as a surrogate of mammography) and breast MRI in 461 high-risk women. We found that CEM detected more cancers than low-energy images and performed as well as breast MRI, while maintaining a safe radiation dose. These results suggest that CEM could be a practical, reliable, and widely accessible option for monitoring women at increased risk of breast cancer, potentially improving early detection and guiding personalized screening strategies.

Background/Objectives: Surveillance of women at increased risk for breast cancer requires high-sensitivity imaging. This study compared contrast-enhanced mammography (CEM) with low-energy CEM (LE-CEM) and breast MRI in this population. Methods: This retrospective analysis included 461 women enrolled in a high-risk imaging protocol (March 2019–October 2022). Lifetime breast cancer risk was estimated using the Tyrer–Cuzick model. All participants underwent CEM and breast MRI ≥ 72 h apart. LE-CEM images were used as a surrogate for digital mammography. Four readers independently interpreted LE-CEM and CEM; a separate group of four readers interpreted MRI. Diagnostic performance was assessed using sensitivity, specificity, and area under the receiver operating characteristic curve (AUC) within a multireader, multicase framework. Noninferiority testing was performed with Δ = 0.05. Mean glandular dose (MGD) for CEM was recorded. Results: CEM showed higher sensitivity than LE-CEM (83.0% vs. 68.9%, p < 0.001) with similar specificity (90.8% vs. 92.5%, p = 0.176). Mean AUC increased from 0.856 for LE-CEM to 0.936 for CEM (p < 0.001). CEM and MRI showed comparable sensitivity (82.9% vs. 86.1%, p = 0.547), specificity (90.8% vs. 86.5%, p = 0.318), and mean AUC (0.936 vs. 0.933; p = 0.839), confirming noninferiority of CEM. MGD per view ranged from 1.56 to 3.10 mGy. Conclusions: Contrast-enhanced mammography provides diagnostic accuracy equivalent to breast MRI and superior to LE-CEM, with acceptable radiation dose, supporting its use for surveillance in women at increased breast cancer risk.

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