Research in context
Evidence before this study
We searched PubMed and MEDLINE for peer-reviewed, original studies published in English until Feb 22, 2017, using the search terms “PSMA”, “Prostate Specific Membrane Antigen”, “positron emission tomography”, and “PET”. We also reviewed key journals and congress abstracts in the fields of nuclear medicine and urologic oncology. We found data suggesting that prostate-specific membrane antigen (PSMA) PET-CT is an important advance for imaging prostate cancer, particularly in the setting of recurrent cancer. Data were limited by retrospective or single-centre design, without comparison with a reference standard or conventional imaging. No prospective or randomised data for primary staging were available. Therefore, we designed a phase 3 imaging trial to investigate the utility of this novel modality. Several studies have been published after the proPSMA study commenced, but high-quality, prospectively collected data comparing PSMA PET-CT with conventional imaging do not exist to date.
Added value of this study
This randomised phase 3 study provides compelling evidence that PSMA PET-CT has better accuracy, with consequent management change, fewer equivocal results, and lower radiation exposure compared with current standard-of-care imaging with CT and bone scanning in men with newly-diagnosed prostate cancer.
Implications of all the available evidence
Collective data from this prospective imaging study and other series provides data that PSMA PET-CT is better than and can replace conventional imaging with CT and bone scan for staging men with high-risk prostate cancer before surgery or radiotherapy with curative intent. Existing guidelines should be reviewed in light of these findings. Further health-economic analyses are required to support potential reimbursement to enable widespread access to PSMA PET-CT for men.