Predictive value of parameters derived from ¹⁸F-PSMA-1007 PET/MR for risk stratification and metastatic status in newly diagnosed prostate cancer

Objective To explore the predictive value of the parameters derived from ¹⁸F-prostate specific membrane antigen (PSMA)-1007 PET/MR for risk stratification and metastatic status in patients newly diagnosed with prostate cancer (PCa).

Methods A retrospective analysis was conducted on the images and clinical data of 46 patients newly diagnosed with PCa (age (69.9±9.7) years, range: 49–86 years) who underwent ¹⁸F-PSMA-1007 PET/MR in the First Affiliated Hospital of Naval Medical University from April 2023 to January 2024. In accordance with the recommendations from the National Comprehensive Cancer Network of the United States and the tumor, node, metastasis staging system of the American Joint Committee on Cancer, the patients were divided into binary groups: intermediate-to-low-risk and high-risk groups, and nonmetastasis and metastasis groups. Mann-Whitney U test was used to compare intergroup differences in maximum standardized uptake value (SUV_max), minimum apparent diffusion coefficient (ADC_min), tumor volume of PSMA (PSMA-TV), and total lesion of PSMA (TL-PSMA) of primary lesions. The receiver operating characteristic (ROC) curve was used to evaluate the predictive efficacy of the parameters derived from PET/MR for high-risk PCa and metastatic PCa.

Results Among the 46 patients with PCa, 10 (21.7%) in the intermediate-to-low-risk group, and 36 (78.3%) were in the high-risk group; 31 (67.4%) in the nonmetastasis group, and 15 (32.6%) in the metastasis group. Statistically significant differences (Z=−3.888 to 3.955, all P<0.05) in SUV_max (28.6 (17.9, 44.0) vs. 14.7 (9.7, 22.8)), ADC_min (0.733 (0.647, 0.822)×10⁻³ mm²/s vs. 0.951 (0.906, 1.009)×10⁻³ mm²/s), PSMA-TV (17.5 (11.8, 46.0) cm³ vs. 5.5 (2.6, 10.1) cm³), and TL-PSMA (155.0 (78.2, 342.0) cm³ vs. 29.8 (16.4, 45.4) cm³) were observed between the high-risk and intermediate-to-low-risk groups. Statistically significant differences (Z=−3.234 to 2.542, all P<0.05) in SUV_max (42.4 (20.0, 50.0) vs. 20.4 (11.9, 33.8)), ADC_min (0.661 (0.578, 0.743)×10⁻³ mm²/s vs. 0.808 (0.727, 0.949)×10⁻³ mm²/s), PSMA-TV (34.1 (12.6, 64.2) cm³ vs. 11.7 (7.5, 18.6) cm³), and TL-PSMA (260.1 (117.7, 495.0) cm³ vs. 78.1 (33.3, 159.1) cm³) were also found between the metastasis and nonmetastasis groups. ROC curve analysis demonstrated that the areas under curve (AUCs) for predicting high-risk PCa using SUV_max, ADC_min, PSMA-TV, and TL-PSMA were 0.783 (95%CI: 0.637–0.891), 0.906 (95%CI: 0.782–0.972), 0.913 (95%CI: 0.791–0.976), and 0.908 (95%CI: 0.786–0.973), respectively. The AUCs for predicting metastatic PCa using SUV_max, ADC_min, PSMA-TV, and TL-PSMA were 0.733 (95%CI: 0.582–0.853), 0.797 (95%CI: 0.652–0.901), 0.706 (95%CI: 0.554–0.831), and 0.723 (95%CI: 0.571–0.844), respectively.

Conclusion The parameters derived from ¹⁸F-PSMA-1007 PET/MR can be used as imaging markers for the preoperative, noninvasive prediction of risk stratification and metastatic status in patients newly diagnosed with PCa.