ABSTRACT
ObjectiveTo investigate the serum prostate-specific antigen (tPSA),serum free PSA to total PSA ratio (f/tPSA),prostate volume (PV) and prostate-specific antigen density (PSAD) in early prostate cancer (PCa) diagnosis.MethodsRetrospective analysis was performed on serum PSA values and related test results from 252 cases of BPH patients and 49 patients with PCa.Prostate volume (PV) was measured by transrectal ultrasound (TRUS),and the f/tPSAand PSAD values were calculated.The differences of serum tPSA,f/tPSA,PV,and PSAD between BPH and PCa group were compared,the area under the ROC curve was used to evaluate these four indicators for its diagnostic sensitivity and diagnostic specificity.ResultsThe values of tPSA,PSAD in PCa group were significantly higher than BPH group ( P ＜0.05),while the values of f/tPSA,PV in PCa group were significantly lower than BPH group ( P ＜0.01orP ＜0.05).The ROC area showed that serum tPSA(0.8013),f/tPSA(0.7390),PV(0.5613) had lower diagnosis value than PSAD(0.9214) in early prostate cancer ( PSAD ＞ tPSA ＞ f/tPSA ＞ PV).When the upper limit of normal PSA was set to take 4ng/ml,the sensitivity was 91.49％,diagnostic specificity was 51.05％.When the f/tPSA threshold set to 0.16,the diagnostic sensitivity was 57.78％,diagnostic specificity was 78.72％.When PSAD threshold was set to 0.15,diagnostic sensitivity was 88.24％,diagnostic specificity was 81.52％.ConclusionsPSA,f/tPSA and PSAD are indicators for biopsy or followup in early diagnosis of prostate cancer.In particular,the diagnostic value of PSAD has higher sensitivity and specificity than PSA and f/tPSA in the diagnosis of prostate cancer.