Comparison of 68Ga-PSMA PET/CT and 18F-FDG PET/CT in the diagnosis of biochemical recurrence of prostate cancer / 中华核医学与分子影像杂志

ABSTRACT

Objective:To compare the diagnostic efficacy of 68Ga-prostate specific membrane antigen (PSMA)-11 PET/CT and 18F-flurodeoxyglucose (FDG) PET/CT in patients with prostate cancer biochemical recurrence after radical prostatectomy. Methods:A total of 82 patients ((76.7±7.1) years) with clinical diagnosis of biochemical recurrence after radical prostatectomy from June 2018 to August 2019 in Renji Hospital, School of Medicine, Shanghai Jiao Tong University were included. All patients underwent 68Ga-PSMA-11 PET/CT and 18F-FDG PET/CT within 2 weeks. The diagnostic efficacy of 2 methods were compared, and the detection rates were also compared among patients with different total prostate specific antigen (tPSA) levels (tPSA≤0.5 μg/L, 0.5 μg/L<tPSA≤1.0 μg/L, 1.0 μg/L<tPSA≤2.0 μg/L, 2.0 μg/L<tPSA≤4.0 μg/L, 4.0 μg/L<tPSA≤10.0 μg/L, tPSA>10.0 μg/L). Logistic regression analysis was applied to analyze the factors affecting the detection rate of 68Ga-PSMA-11 PET/CT. Results:A total of 57 patients (98 regional lesions) were detected by 68Ga-PSMA-11 PET/CT and/or 18F-FDG PET/CT. Patients were followed up for 2-12 months, and 50 patients (81 lesions) were found to have recurrence or metastasis of prostate cancer. The patient-related detection rate, sensitivity and positive predictive value of 68Ga-PSMA-11 PET/CT and 18F-FDG PET/CT were 68.29%(56/82) vs 36.59%(30/82), 96.00%(48/50) vs 52.00%(26/50), 85.71%(48/56) vs 86.67%(26/30); the detection rates were significantly different ( χ2=19.756, P<0.05). The patient-related detection rates of 68Ga-PSMA PET/CT were higher than those of 18F-FDG PET/CT under different tPSA levels, especially when 0.5 μg/L<tPSA≤1.0 μg/L (10/18 vs 2/18). The detection rate of 68Ga-PSMA PET/CT was significantly correlated with tPSA level (odds ratio( OR)=1.319, 95% CI: 1.088-1.598), age ( OR=1.141, 95% CI: 1.051-1.238), preoperative staging ( OR=1.357, 95% CI: 1.052-2.439), and postoperative treatment ( OR=1.134, 95% CI: 1.020-1.917) (all P<0.05). Conclusion:68Ga-PSMA PET/CT has better detection advantages than 18F-FDG PET/CT in diagnosing biochemical recurrence after radical prostatectomy.