Combined forced diuresis and late acquisition on [68Ga]Ga-PSMA-11 PET/CT for biochemical recurrent prostate cancer: a clinical practice-oriented study

Objectives Increased detection of prostate cancer (PCa) recurrences using [ 68 Ga]Ga-PSMA-11 PET/CT has been reported by adding forced diuresis or late-phase imaging to the standard protocol. However, the combination of these procedures in the clinical setting is still not standardized. Methods One hundred prospectively recruited biochemical recurrent PCa patients were restaged with dual-phase [ 68 Ga]Ga-PSMA-11 PET/CT from September 2020 to October 2021. All patients received a standard scan (60 min), followed by diuretics (140 min) and a late-phase abdominopelvic scan (180 min). PET readers with low ( n = 2), intermediate ( n = 2), or high ( n = 2) experience rated (i) standard and (ii) standard + forced diuresis late-phase images in a stepwise fashion according to E-PSMA guidelines, scoring their level of confidence. Study endpoints were (i) accuracy against a composite reference standard, (ii) reader’s confidence level, and (iii) interobserver agreement. Results Forced diuresis late-phase imaging increased the reader’s confidence category for local and nodal restaging (both p