The Use Of PSAD In Detecting Prostate Cancer In Patients With PSA In Gray Zone

Aim:To investigate the utility of prostate-specific antigen density for detecting prostate cancer in men with serum PSA levels of 4-10 ng/mL.Methods:Between January 2003 and November 2007,237 men(aged 48-84 years,median 71)with total PSA levels of 4-10 ng/mL participated in a protocol for prostate-cancer screening.Eligible patients were recommended for transrectal ultrasonography(TRUS)-guided prostate biopsies after measuring prostate volumes transrectally.The diagnostic value of PSA levels and the free-to-total PSA ratio (f/tPSA),PSA densities(PSAD)were compared using receiver operating characteristic analysis. Results:Prostate cancer was diagnosed in 44(18.6%)of the 237 men who had biopsies.There were significant differences between the groups in the prostate volumes determined by TRUS, PSAD,PSA levels and f/tPSA,whereas there was no significant difference in patient age.The area under the curve(AUC)of PSA(0.6786)and PSAD(0.717)was similar and significantly greater than that of f/tPSA(AUC 0.329).PSAD was a significantly better indicator of prostate cancer than f/tPSA.The sensitivity and specificity of PSA density at a cutoff of 0.134 ng/mL~2 was 90%and 33.7%,respectively.Conclusion:PSAD was a better predictor of prostate cancer in Chinese men with PSA levels of 4-10 ng/mL,especially those who have had prior ultrasound-determined measurements of prostate volume.Our data suggest that different PSAD cutoffs may need to be defined for Chinese.