Clinical application of PRIMARY score in diagnosing clinically significant prostate cancer: a comparative study using 68Ga-PSMA-11 and 18F-PSMA-1007 positron emission tomography/computed tomography

Background: F)-PSMA-1007 PET/CT remains underexplored. This study aimed to assess the diagnostic performance of the PRIMARY score on both tracers and compare their effectiveness in identifying clinically significant prostate cancer (csPCa). Methods: This retrospective study included 192 patients who underwent PSMA PET/CT and systematic biopsy. PRIMARY scores were categorized as PET-positive (score 3-5) or PET-negative (score 1-2). PSMA uptake patterns were categorized as no pattern, diffuse transition (TZ)/central zone (CZ) (non-focal), focal TZ, or focal peripheral zone (PZ). Diagnostic metrics [sensitivity, specificity, accuracy, positive predictive value (PPV), negative predictive value (NPV)] were calculated against histopathology. DeLong test was used to compare the areas under the receiver operating characteristic (ROC) curves (AUCs) of the PRIMARY score and maximum standardized uptake value (SUVmax). Univariate logistic regression assessed associations between SUVmax and csPCa by pattern, reporting odds ratios (ORs) with 95% confidence intervals (CIs). Results: F-PSMA-1007 PET/CT group, a significant association between SUVmax and csPCa was observed in the focal PSMA pattern (P