Objective: We aimed to evaluate predictive abilities of percent free prostate specific antigen (PSA) and PSA density (PSAD) in the diagnosis of prostate cancer, alone and in combination.
Materials and Methods: 439 patients who had trans-rectal ultrasound guided prostate bi-opsy and with a PSA value between 2.5 and 10 ng/ml, normal digital rectal examination fin-dings, and without any history of an interven-tion, active infection or drug use that would af-fect PSA levels were included in our study. All patients’ pre-biopsy total PSA (tPSA), free PSA (fPSA), age, prostate volume and biopsy patho-logy reports were reviewed. We obtained percent free PSA by dividing fPSA to tPSA and obtained PSAD by dividing tPSA to prostate volume. The cut-off value for percent free PSA was 20% and 15% for PSAD. According to pathology results, the patients were divided into two groups as BPH and prostat cancer.
Results: The mean age, tPSA, fPSA, prostate volume, percent free PSA, PSAD values of the pa-tients were; 64 ± 8.4 year, 6.3 ± 1.93 ng/ml, 1.28 ± 0.77 ng/ml, 56.5 ± 25.9 ml, 20.2% ± 9.7 and 13.6% ± 7.5, respectively. Between the two gro-ups, fPSA (p=0.002), prostate volume (p=0.000), percent free PSA (p=0.002) and PSAD (p=0.001) were significantly different while age (p=0.311) and tPSA (p=0.691) were not.
Sensitivity of percent free PSA was 73%, spe-cificity 45%, positive predictive value (PPV) 21%, negative predictive value (NPV) 89% and accuracy 50%. Sensitivity of PSAD was 57%, specificity 74%, PPV 31%, NPV 89% and accuracy 71%. Sensitivity of using both parameters in combination was 50%, specificity 79%, PPV 33%, NPV 88% and accuracy 74%.
Conclusion: In the prediction of prostate cancer, using percent free PSA and PSAD in combination is more efficient than using the-se parameters alone.
Key Words: Prostate cancer, PSA density, percent free PSA
Abstract
Objective: We aimed to evaluate predictive abilities of percent free prostate specific antigen (PSA) and PSA density (PSAD) in the diagnosis of prostate cancer, alone and in combination.
Materials and Methods: 439 patients who had trans-rectal ultrasound guided prostate bi-opsy and with a PSA value between 2.5 and 10 ng/ml, normal digital rectal examination fin-dings, and without any history of an interven-tion, active infection or drug use that would af-fect PSA levels were included in our study. All patients’ pre-biopsy total PSA (tPSA), free PSA (fPSA), age, prostate volume and biopsy patho-logy reports were reviewed. We obtained percent free PSA by dividing fPSA to tPSA and obtained PSAD by dividing tPSA to prostate volume. The cut-off value for percent free PSA was 20% and 15% for PSAD. According to pathology results, the patients were divided into two groups as BPH and prostat cancer.
Results: The mean age, tPSA, fPSA, prostate volume, percent free PSA, PSAD values of the pa-tients were; 64 ± 8.4 year, 6.3 ± 1.93 ng/ml, 1.28 ± 0.77 ng/ml, 56.5 ± 25.9 ml, 20.2% ± 9.7 and 13.6% ± 7.5, respectively. Between the two gro-ups, fPSA (p=0.002), prostate volume (p=0.000), percent free PSA (p=0.002) and PSAD (p=0.001) were significantly different while age (p=0.311) and tPSA (p=0.691) were not.
Sensitivity of percent free PSA was 73%, spe-cificity 45%, positive predictive value (PPV) 21%, negative predictive value (NPV) 89% and accuracy 50%. Sensitivity of PSAD was 57%, specificity 74%, PPV 31%, NPV 89% and accuracy 71%. Sensitivity of using both parameters in combination was 50%, specificity 79%, PPV 33%, NPV 88% and accuracy 74%.
Conclusion: In the prediction of prostate cancer, using percent free PSA and PSAD in combination is more efficient than using the-se parameters alone.
Key Words: Prostate cancer, PSA density, percent free PSA