RESUMO
Objective:To evaluate the clinical application potential of a novel prostate specific membrane antigen (PSMA) targeted PET tracer 68Ga-PSMA-NYM032 in patients diagnosed initially with prostate cancer. Methods:A total of 63 patients (age (68.7±8.7) years) with suspected prostate cancers who received 68Ga-PSMA-NYM032 PET/CT imaging in Affiliated Hospital of Jiangnan University between March 2022 and January 2023 were enrolled prospectively. The diagnostic efficiency of 68Ga-PSMA-NYM032 PET/CT imaging was evaluated in a patient-centered manner. The ROI was drawn to obtain SUV max by semi-quantitative analysis with visual analysis, and the diagnostic threshold of SUV max was obtained by ROC curve analysis. The correlations of SUV max in primary foci with total prostate specific antigen (tPSA) and Gleason score (GS) were analyzed by Spearman rank correlation analysis. Based on the D′Amico risk stratification (prostate specific antigen (PSA)>20 μg/L and ≤20 μg/L, GS>7 and ≤7), the detection rates of metastases by 68Ga-PSMA-NYM032 PET/CT imaging in different stratifications were analyzed by Fisher exact test, and the differences between SUV max of metastases in different stratifications were determined by Mann-Whitney U test. Results:The accuracy of 68Ga-PSMA-NYM032 PET/CT imaging was 92.06%(58/63), the sensitivity was 96.55%(28/29), the specificity was 88.24%(30/34), the positive predictive value was 87.50%(28/32), the negative predictive value was 96.77%(30/31), and the optimal SUV max threshold was 6.9. 68Ga-PSMA-NYM032 showed varying degrees of high uptake in the primary foci of prostate cancer, and SUV max were positively correlated with tPSA and GS ( rs values: 0.657, 0.592, P values: <0.001, 0.001). Stratified analysis showed a statistically significant difference in the detection rate of bone metastases by 68Ga-PSMA-NYM032 PET/CT between the GS>7 and GS≤7 subgroups (9/17 vs 1/12; P=0.019), while no statistical significances were observed in the detection rates of bone metastases or lymph node metastases of another subgroups (all P>0.05). In addition, none of the differences in SUV max of metastases in patients with different stratifications were statistically significant ( z value: from -1.57 to -0.50, all P>0.05). Conclusions:68Ga-PSMA-NYM032 PET/CT imaging has good diagnostic efficacy for prostate cancer, and it may provide a new strategy for the precise diagnosis and treatment of prostate cancer. Besides, GS stratification may affect the detection rate of bone metastases by 68Ga-PSMA-NYM032 PET/CT imaging.