Diagnostic Value of f/tPSA Versus PSAD for tPSA Gray Zone Prostate Cancer with Normal Digital Rectal Examination: A Meta-Analysis

Objective Performing a meta-analysis to compare the diagnostic value of the ratio of free to total prostate-specific antigen （f/tPSA） with prostate specific antigen density （PSAD） for prostate cancer patients who had a negative normal digital rectal examination （DRE） and PSA level between 4 and 10 ng/mL. Methods PubMed, EMBASE, Web of Science, Cochrane Library, and Chinese Biomedical Literature Database were searched to identify related studies up to March 2014. Two independent reviewers performed the literature review and data extraction. Eligible studies presented data on diagnostic value of prostate cancer by f/tPSA and PSAD. The quality of included studies was assessed according to standard Quality Assessment of Diagnosis Accuracy Studies （QUADAS） criteria. The pooled data were analyzed with Meta-DiSC1.4 software. Results Seven studies including 700 prostate cancer patients with a negative DRE and PSA level between 4~10 ng/mL were included. The pooled sensitivity, specificity and the Q index of f/tPSA in the diagnosis of prostate cancer were 0.70 （95%CI 0.62~0.77）, 0.62 （95%CI 0.59~0.66） and 0.674 4, respectively, with comparison of those of PSAD being 0.70 （95%CI 0.62~0.77）, 0.68 （95%CI 0.65~0.72） and 0.729 1, respectively. The areas under the receiver operating characteristic curve （AUROC） of f/tPSA and PSAD were 0.726 7 and 0.792 2, respectively （P>0.05 by the Z-statistic）, and no statistically significance was found. Conclusion The diagnostic value of f/tPSA and PSAD had no significant difference for prostate cancer patients with a normal DRE and PSA level between 4~10 ng/mL.