Bringing clarity or confusion? The role of prostate-specific membrane antigen positron-emission/computed tomography for primary staging in prostate cancer.

Abstract

The use of 68Ga-labelled prostate-specific membrane antigen (PSMA) positron-emission tomography (PET)/CT for staging prostate cancer in Australia has reached almost plague-like proportions. Despite what must be admitted is little high-level evidence to guide us in the accuracy or appropriateness of this imaging technique for either primary staging or prostate cancer recurrence, hundreds of these scans are being performed every week around Australia, and in many cases we simply do not know what to do with the results. We performed the first such scan at our centre in Melbourne in August 2014, and were soon receiving 10 requests per day, with patients waiting up to 3 months to be scanned. Fast-forward 2 years, and there are now eight centres offering PSMA PET/CT in Melbourne, a city of 4.5 million people. Scans can be obtained within 24 h of referral and costs have dropped to €500. A similar situation exists in Germany where this imaging method was pioneered, and interest is also growing in Belgium, Italy, India and a number of other countries (the USA being a notable exception). But do we really understand the impact of the decision to perform PSMA/PET scanning, and do we have enough evidence to guide us on the most appropriate setting for its use?