Ga-68-PSMA PET/CT Uptake in the Ureter Caused by Ligand Expression in Urothelial Cancer

摘要

Ga-68-PSMAPET/CT has become awell-established imagingmodality to detect prostate cancer (PCa) metastases in biochemical recurrence. Despite its claimed specificity for PCa, Ga-68-PSMA uptake in tissues unrelated to PCa, particularly in the neovascular tissue of other cancers, has been reported in numerous studies. A 73-year-old man underwent Ga-68-PSMA PET/CT for biochemical recurrence of PCa 7 years after radical prostatectomy. The Ga-68-PSMA PET/CT showed 1 lesion with PSMA uptake in the distal left ureter. Histology revealed a low-grade noninvasive papillary urothelial carcinoma. By immunohistochemistry, PSMA expression was observed in the neoplastic urothelial cells and in the vessels of the papillary structures.