The Impact of prostate – Specific Antigen Density In Predicting Prostate Cancer

Abstract

The objective of this study is to evaluate the impact of prostate-specific antigen density ( PSDA ) when serum levels of prostate-specific antigen ( PSA ) are less than 10 ng\ml in predicting prostate cancer. We retrospectively analyzed 134 patients who underwent trans rectal ultrasound ( TRUS )-guided prostate biopsies according to Cooner's algorithm. Histopathological examination revealed prostate cancer ( PCa ) in 22 ( 16% ) and begin prostatic hypertrophy ( BPH ) in 112 ( 84% ) patients.

Five patients ( 23% ) with PCa had PSAD<0.15 of whom 3 had PSA<4 ng\ml and 2 had PSA between 4 and 10 ng\ml. In the BPH group, 60 patients ( 54% ) had PSAD below 0.15 whereas 52 patients ( 46% ) had PSAD over 0.15 . with 0.15 as the cutoff level of PSAD, the sensitivity and specificity of PSAD was found as 77 and 54%, respectively. In this patient population, PSA with the cutoff level of 4 ng\ml has sensitivity and specificity level of 77 and 33% respectively. According to these result, a statistically significant difference was found between PSA and PSAD only in terms of diagnostic specificity ( chi-square, P<0.05 ) . There were 29 patients with negative digital rectal examination ( DRE ) and TRUS and PSA 4-10 ng\ml who underwent biopsy because of PSAD>0.15 . no cancer was detected in this group of patients, suggesting that biopsy in this subgroup may be unnecessary.