When prostate cancer comes back after radiation, finding it early is crucial for the right treatment. This review looked at how two common scans—mpMRI and PSMA PET—work for spotting a return.
The scans work differently. mpMRI is good at finding tumors inside the prostate, but it can miss some and sometimes underestimates how many tumors are there, especially after brachytherapy. PSMA PET is very good at finding recurrent tumors, but it might miss tiny ones or tumors that don't show up well on the scan.
When both scans agree, the chance that cancer is truly back is very high—about 98%. This combination helps doctors target biopsies better and decide who might benefit from further treatment. The review looked at patients with suspected radiorecurrent prostate cancer, but the exact number of people studied wasn't reported.
The evidence comes from 10 studies, some planned and some looking back at records, so the results are promising but not definitive. Doctors still need a tissue biopsy to confirm cancer before any local salvage treatment.