Resolving a global challenge in breast imaging: Efficacy of contrast-enhanced digital mammography in global asymmetry

Global asymmetry is defined as asymmetry involving more than one quadrant of the breast without an associated mass, suspicious calcifications, or architectural distortion. While often benign, its diffuse nature frequently leads to diagnostic dilemmas, necessitating the exclusion of malignancies. This case series reviews four patients presenting with global asymmetry as vague areas of suspicious heterogeneity on conventional mammography, where initial assessment through mammography and ultrasound led to categorization as breast imaging-reporting and data system (BI-RADS) 3 or 4, raising suspicion for malignancy. To resolve these diagnostic ambiguities, all four patients subsequently underwent contrast-enhanced digital mammography (CEDM). The CEDM-subtracted images consistently demonstrated no enhancement in the regions of asymmetry, reflecting the definitive absence of neoangiogenesis. This confirmed the benign nature of the asymmetry, and consequently, the BI-RADS categories for all patients were revised to BI-RADS 2. Although a biopsy was ultimately performed in one case upon the patient’s strong request, the histopathology confirmed benign fibroglandular tissue, underscoring the technique’s utility. Hence, due to its very high negative predictive value for eliminating neoangiogenesis and the probability of malignancy, CEDM can be used as a crucial problem-solving tool in cases of indeterminate global asymmetry.