PSMA-ya.

Top Line: Is PSMA-PET more accurate than CT and bone scan at identifying metastatic disease in men with high risk prostate cancer?

The Study: At this point, advanced imaging techniques for prostate cancer, such as fluciclovine and PSMA, are mostly limited to patients with recurrent disease. There are no randomized trials, though, for using PSMA for initial staging. In the proPSMA trial, Australian men (n=339) with localized, high risk prostate cancer were randomized to workup with standard CT and bone scan or PSMA-PET. After initial imaging, patients with no, equivocal, or fewer than 3 sites of metastasis crossed-over for additional imaging with the opposite modality. By 6 months after enrollment and treatment, 30% of men were found to meet the reference standard criteria for either nodal or distant metastasis. The accuracy of diagnosing both nodal or distant metastatic disease was much better with initial PSMA-PET (AUC 92%) than with standard imaging (AUC 65%). Among men who had initial PSMA-PET, patterns of metastasis were 20% pelvic nodal, 10% bone, 9% para-aortic, and 1% visceral. Initial PSMA-PET had fewer equivocal findings (7% vs 23%) and also resulted in a change in management for more men (28% vs 15%). While standard imaging added little to PSMA-PET findings, 27% of men who had initial standard imaging went on to have major findings on the second-line PSMA-PET.

TBL: Initial staging with PSMA-PET is more accurate than CT and bone scan at identifying occult metastatic disease in men with high risk prostate cancer. | Hofman, Lancet 2020