[Ga-68-PSMA PET/CT for prostate cancer]

Prostate-specific membrane antigen (PSMA) is expressed as a cell surface protein physiologically in the prostate and can be found in all stages of prostate cancer. Even in castration-resistant prostate cancers, this overexpression of PSMA occurs. Due to the enzymatic activity of PSMA it was possible develop specific inhibitors from which "small molecule" radiopharmaceuticals were derived. By coupling the specific binding motif glutamate-urea-lysine with the chelator HBED-CC, which complexes Ga-68 very effectively, a new radiopharmaceutical is available for Ga-68-PSMA-PET/CT. According to the first results in patients with prostate carcinoma, this new diagnostic tool exhibited advantages in image quality compared to choline-PET/CT. An initial study demonstrated the higher contrast of the PET signal and an improved diagnostic accuracy. The properties of even further new PSMA PET radiopharmaceuticals can be of increasing importance for the diagnostic work-up of prostate cancer in all stages. In conjunction with therapeutic PSMA radiopharmaceuticals, a new field of theragnostics is opened.