Breast Inflammation Mimicking Breast Cancer on Multimodality Breast Imaging

Extract

Inflammatory lesions of the breast are diverse and challenging to diagnose clinically and radiographically given their nonspecific presentations. A 44-year-old average-risk woman presented with subtle trabecular thickening on screening mammography in the right breast (Figure 1). During diagnostic work-up, the patient endorsed vague right breast swelling and spontaneous bloody nipple discharge. Diagnostic mammography confirmed trabecular thickening, and subareolar ultrasound revealed only mild duct ectasia. Targeted ultrasound of the upper outer quadrant of the right breast revealed a subtle hypoechoic mass (Figure 2), which underwent ultrasound-guided biopsy and revealed nonspecific inflammation. Because of the presence of spontaneous bloody nipple discharge and questionable imaging–pathology concordance, a breast MRI was performed, which demonstrated extensive non-mass enhancement (NME) and level-one axillary lymphadenopathy (Figure 3). Given that the initial biopsy marker clip was within the anterior aspect of the NME, an MRI-guided biopsy of the posterior aspect of the process was performed, which revealed lobulocentric inflammation with mild epithelial atypia. Ultrasound-guided biopsy of an enlarged axillary lymph node demonstrated only reactive hyperplasia. Surgical excision of the site of atypia and the subareolar region (to address the clinically suspicious nipple discharge) confirmed lobulocentric inflammation and benign duct ectasia, respectively. This case illustrates the importance of breast radiologists’ familiarity with diverse presentations of breast inflammation to assist with imaging–pathology concordance assessments and appropriate follow-up recommendations.