FDG PET/CT in 2 Cases of Primary Urothelial Carcinoma of the Prostate.

Primary prostatic urothelial carcinoma is a very rare aggressive tumor with poor prognosis. We describe FDG PET/CT findings in 2 patients with primary prostatic urothelial carcinoma. In 1 patient, FDG PET/CT showed intense activity of the prostate tumor with extraprostatic invasion. In the other patient, FDG PET/CT showed heterogeneous intense activity of the primary tumor and multiple hypermetabolic metastases in the regional lymph nodes, bone, and lung. Both patients had normal serum total prostate-specific antigen levels. These cases highlight the usefulness of FDG PET/CT in detecting and staging of primary prostatic urothelial carcinoma due to high FDG avidity.