Publikationsrepositorium - Helmholtz-Zentrum Dresden-Rossendorf

PSMA-PET/CT for imaging prostate cancer (PC) has spread worldwide since its clinical introduction in 2011. The majority of experiences have been collected for PSMA-PET-imaging of recurrent PC. Data for primary staging of high-risk PC are highly promising. Meanwhile, a plethora of PSMA-ligands are available for clinical use (e.g. 68Ga-PSMA-11, 68GaPSMA-I&T, 68Ga-PSMA-617, 18F-DCFBC, 18F-DCFPyL, 18F-PSMA-1007, 18F-rhPSMA-7 and 18F-JK-PSMA-7). However, an official approval is available only for 68Ga-PSMA-11 (approved by the US FDA in 2020) and 18F-DCFPyL (approved by the US FDA in 2021).
Recommendations for acquisition times vary from 1-2h p.i. It has been shown that for the majority of tumour lesions, the contrast in PSMAPET/CT increases with time. Therefore, additional late imaging can help to clarify unclear findings. PSMA-PET/CT should be performed prior to commencing an androgen deprivation therapy (ADT) since (long term) ADT reduces the visibility of PC lesions.
Following injection of PSMA-ligands, hydration and forced diuresis are recommended for PSMA-ligands with primarily excretion via the kidneys in order to increase the visibility of tumour lesions adjacent to the urinary bladder.
PSMA-ligands are physiologically taken up in multiple normal organs. For some 18F-labelled PSMA-ligands, presence of unspecific focal bone uptake has been reported. When using these tracers, focal bone uptake
without CT-correlate should be interpreted with great caution. Besides prostate cancer, practically all solid tumors express PSMA in their neovasculature thereby taking up PSMA-ligands, although usually at a lower extent compared to PC. Also multiple benign lesions and inflammatory processes (e.g. lymph nodes) take up PSMA-ligands, also
usually at lower extent compared to PC.