68Ga-PSMA PET/CT Detects a Rare Case of Breast Metastasis from Prostate Cancer.

Positron emission tomography/computed tomography (PET/CT) with Galium-68 prostate-specific membrane antigen (68Ga-PSMA) PET/CT) is a valuable tool for initial staging, recurrence detection, and assessment of treatment response in men with prostate cancer. Metastatic spread to regional and distant lymph nodes, bone, lung and liver is well known and expected in patients with castration-resistant disease. However, the application of a highly sensitive whole-body imaging modality such as 68Ga-PSMA PET/CT can reveal metastatic foci in rare or unusual locations. We present the case of an 82-year-old patient with prostate adenocarcinoma who underwent long-term androgen deprivation therapy. A 68Ga-PSMA PET/CT scan was performed in June 2021 due to significant prostate-specific antigen elevation and revealed disease progression with widespread regional and distant metastases, including a soft-tissue mass in the right breast that demonstrated intense radiotracer uptake; this mass was subsequently resected and histologically confirmed. This case underscores the excellent diagnostic performance of 68Ga-PSMA PET/CT for atypical metastatic sites.