Correlation between PSA kinetics and detection rate of PSMA-PET in the setting of biochemical recurrent prostate cancer: A systematic review and meta-analysis.
71 Background: Serum prostate-specific antigen (PSA) may predict the risk of positive positron emission tomography/computed tomography with radiolabeled prostate-specific membrane antigen (PSMA-PET/CT) in patients with biochemical recurrent prostate cancer (BRPCa). However, to date, there are no clear data regarding the correlation between PSA kinetics and PSMA-PET findings. We performed a systematic review and meta-analysis to provide evidence-based data in this setting. Methods: A comprehensive literature search of studies published through October 2018 in PubMed/MEDLINE, EMBASE and Cochrane library databases was performed. A meta-analysis to establish the detection rate (DR) of PSMA-PET using different cut-off values of PSA doubling time (PSAdt) and a pooled analysis to establish whether shorter PSAdt may predict positive PSMA-PET results was performed in patients with BRPCa. Results: Twelve articles were included in the systematic review and eight articles (including 1398 patients) were selected for the meta-analysis. The pooled DR including 95% confidence intervals (95% CI) of PSMA-PET in restaging prostate cancer (PCa) patients was 72% (95% CI: 60-82%), increasing to 83% (95% CI: 75-90%) when PSAdt was ≤ 6 months and decreasing to 60% (95% CI: 37-80%) when PSAdt was > 6 months. PSAdt ≤ 6 months may predict the positive result of PSMA-PET (pooled odds ratio: 3.22; 95% CI: 1.17-8.88). Statistical heterogeneity among the included studies was found. Conclusions: PSA kinetics, and in particular shorter PSAdt, may be predictor of PSMA-PET positivity in patients with BRPCa. Further larger studies in this setting are warranted.