An Unusual Breast Malignancy Identified on DOTATATE PET-CT

A 45-year-old woman initially presented with rapid-onset Cushing syndrome from ectopic adrenocorticotrophic hormone secretion. A chest CT was performed at an outside institution that demonstrated a 2.9-cm lobulated anterior mediastinal soft tissue mass. A whole-body Ga-68 DOTATATE PET-CT was performed due to high clinical suspicion of a neuroendocrine tumor. The Ga-68 DOTATATE PET-CT demonstrated moderate radiotracer activity within the mediastinal mass, maximum standardized uptake value 4.8. Biopsy of the mass was positive for atypical carcinoid tumor and the mass was resected. Follow-up Ga-68 DOTATATE PET-CT demonstrated a DOTATATE-avid focus in the left breast (Figure 1) that prompted evaluation with dedicated breast imaging. Diagnostic mammogram of the left breast revealed an irregular mass in the left upper outer breast with indistinct margins and pleomorphic calcifications (Figure 2). Targeted ultrasound of the left breast at the 1-o’clock position demonstrated an irregular mass with indistinct margins (Figure 3...