Clinical Significance of Prostate-Specific Antigen Density in Patients with Serum Prostate Specific Antigen between 4 and 10ng/ml

Abstract

Purpose: To examine the usefulness of the prostate-specific antigen (PSA) density for selection of biopsy candidates with serum PSA levels between 4-10ng/ml, and determine the optimal PSA density (PSAD) cut off value for use in clinical practice. Materials and Methods: We retrospectively enrolled 705 patients with serum PSA levels between 4-10ng/ml. The patients were divided into the prostate cancer and the non-prostate cancer groups. The PSA level and PSAD in predicting prostate cancer were compared. A receiver operating characteristic (ROC) curve was generated, and utilized to evaluate the optimal PSAD cut off value. Results: One hundred and nineteen and five hundred and eighty six patients had prostate and non-prostate cancers, respectively, on pathological examination. The mean PSA values were not significantly different; 6.9 and 7.0ng/ml, respectively (p＞0.05). However, the mean PSAD values were 0.168 and 0.213ng/ml/cc; significantly higher in the prostate cancer group than the BPH group (p＜0.05). The ROC curves for the PSA level and PSAD demonstrated superior benefit for the PSAD. The sensitivity, specificity and positive predictive values of a PSAD cut off of 0.15ng/ml/ cc were 73.1, 45.9 and 21.5%, respectively. A PSAD cut off of 0.17ng/ml/cc showed the highest sensitivity and specificity, with sensitivity, specificity and positive predictive values of 63.9, 59.2 and 24.1%, respectively. Conclusions: The PSAD seems to be useful in the selection of biopsy candidates with serum PSA levels between 4-10ng/ml, and a PSAD cut off of 0.17ng/ml/cc would seem to be preferable to 0.15ng/ml/cc. (Korean