Restaging the Biochemical Recurrence of Prostate Cancer with [(68)Ga]Ga-PSMA-11 PET/CT: Diagnostic Performance and Impact on Patient Disease Management

SIMPLE SUMMARY: We aimed to evaluate the diagnostic performance, impact on patient disease management, and therapy efficacy prediction of [(68)Ga]Ga-PSMA-11 PET/CT on 294 patients with biochemical recurrence of prostate cancer. We established a composite standard of truth for the imaging based on all clinical data available collected during the follow-up period with a median duration of follow-up of 17 months. Using this methodology, we found that the overall per-patient sensitivity and specificity were both 70%, the patient disease management was changed in 68% of patients, and that [(68)Ga]Ga-PSMA-11 PET/CT impacted this change in 86% of patients. The treatment carried out on the patient was considered effective in 78% of patients; in 89% of patients when guided by [(68)Ga]Ga-PSMA-11 PET/CT versus 61% of patients when not guided by [(68)Ga]Ga-PSMA-11 PET/CT. ABSTRACT: Background: Detection rates of [(68)Ga]Ga-PSMA-11 PET/CT on the restaging of prostate cancer (PCa) patients presenting with biochemical recurrence (BCR) have been well documented, but its performance and impact on patient management have not been evaluated as extensively. Methods: Retrospective analysis of PCa patients presenting with BCR and referred for [(68)Ga]Ga-PSMA-11 PET/CT. Pathological foci were classified according to six anatomical sites and evaluated with a three-point scale according to the uptake intensity. The impact of [(68)Ga]Ga-PSMA-11 PET/CT was defined as any change in management that was triggered by [(68)Ga]Ga-PSMA-11 PET/CT. The existence of a PCa lesion was established according to a composite standard of truth based on all clinical data available collected during the follow-up period. Results: We included 294 patients. The detection rate was 69%. Per-patient sensitivity and specificity were both 70%. Patient disease management was changed in 68% of patients, and [(68)Ga]Ga-PSMA-11 PET/CT impacted this change in 86% of patients. The treatment carried out on patient was considered effective in 89% of patients when guided by [(68)Ga]Ga-PSMA-11 PET/CT versus 61% of patients when not guided by [(68)Ga]Ga-PSMA-11 PET/CT (p < 0.001). Conclusions: [(68)Ga]Ga-PSMA-11 PET/CT demonstrated high performance in locating PCa recurrence sites and impacted therapeutic management in nearly two out of three patients.