Clinical use of prostate-specific antigen density in treatment decision for localized prostate cancer

Abstract

4719 Background: Current treatment of localized Prostate cancer includes different options: Surgery, Radiotherapy or Watchful Waiting (WW). It is well known that surgery treatment is inappropriate when extrapostatic disease (EPD) exists. However, to date, still 25–33% of prostatectomies are shown to be EPD on pathological examination. An explanation for that might be the lack of a good imaging diagnostic test and the inaccuracy of the Gleason and prostatic specific antigen (PSA) as pathological predictors. PSA is not a good predictor mainly due to the contribution of non tumoral prostatic volume to its serum levels. On contrary, it has been suggested that PSA density (PSAD) values are not influenced by non tumoral prostatic volume, thus, becoming more useful. The purpose of the present study was to evaluate whether PSAD might have a role in the treatment decision making. Methods: The cases of 103 consecutive patients who underwent Radical Prostatectomy were reviewed. Preoperative PSA and PSAD were obtained. PSAD was calculated according to the formula: PSAD = serum PSA / prostatic volume determined by TRUS (prolate ellipse formula). Currently accepted PSA cut-off of 10 was compared with PSAD cut-off of 0.15 and 0.20 to determine its accuracy in detecting OCD. Results: The pathological examinations of the 103 prostatectomy specimens revealed EPD in 26 cases (25%). Using a PSA cut-off < 10 resulted in 59 out of 73 patients (80%) with confirmed OCD. On contrary, PSAD cut-off < 0.15 and < 0.20, resulted in 26/27 (96%) and 41/46 (89%) patients, respectively, with OCD. Conclusions: PSAD is a more accurate marker to discriminate OCD than PSA and, therefore, may lead to a more appropriate treatment decision making. No significant financial relationships to disclose.