Objective
To assess the European Association of Urology (EAU) risk groups for biochemically recurrent (BCR) prostate cancer relative to PSMA-PET status and oncological outcomes.
Patients and Methods
A retrospective analysis of a study that incorporated PSMA PET for men with BCR after radical prostatectomy (RP) was undertaken. EAU risk groups were considered relative to clinical variables, PSMA PET findings, and deployment of salvage radiation treatment (SRT). The primary oncological outcome was event-free survival (EFS) and analysed relative to clinical and imaging variables. An “event” occurred if PSA rose > 0.2ng/ml above nadir or additional therapies were introduced.
Results
137 patients were included, with most high EAU risk (76%) and/or low PSA (80% <0.5ng/ml) at time of PSMA PET. EAU risk was not associated with PSMA PET regional nodal/distant metastases. Regional nodal/distant metastasis on PSMA PET (compared to negative/local recurrence; HR 2.2; p=0.002) and SRT use (versus no SRT; HR 0.44, p=0.004) were associated with EFS. High EAU risk was not significantly associated with worse EFS (HR 1.7, p=0.12) compared to low EAU risk. Among patients who received SRT, both regional/distant metastasis on PSMA PET (HR 3.1, p<0.001) and high EAU risk (HR 2.9, p=0.04) were independently associated with worse EFS, which was driven by high EAU risk patients with regional/distant metastasis (38%; HR 3.1; p=0.001).
Conclusions
In men with post-RP BCR, PSMA-PET findings and receipt of SRT predicted EFS. In men receiving SRT, PSMA status combined with EAU risk grouping was most predictive of EFS. These findings suggest that the EAU risk groups could be improved with the addition of PSMA PET.
