PSA、f／tPSA、PV和PSAD在前列腺癌早期诊断中的比较

Significance of serum PSA, f/tPSA, PV, PSAD in early diagnosis of prostate cancer

目的探讨血清总前列腺特异抗原（tPSA）、血清游离PSA与总PSA比值（f／tPSA）、前列腺体积（PV）及前列腺特异抗原密度（PSAD）在早期前列腺癌（PCa）诊断中的价值。方法回顾性分析252例BPH患者和49例PCa患者的血清PSA值及相关检测结果。经直肠超声（TRUS）测定前列腺体积（PV），并计算f／tPSA和PSAD值。比较BPH和PCa组间血清tPSA、f／tPSA、PV和PSAD检测结果间的差异，分析这四项指标的ROC曲线下面积、诊断敏感性和诊断特异性的差异。结果PCa组患者tPSA、PSAD明显高于BPH组（P〈0．05），而f／tPSA、PV中PCa组患者明显低于BPH组（P〈0．01或P〈0．05）。ROC曲线下面积，血清tPSA（0．8013）、f／tPSA（0．7390）、PV（0．5613）三者检测诊断价值较低，PSAD（0．9214）值的检测诊断价值较前三者明显，即PSAD〉tPSA〉f／tPSA〉PV。当PSA取正常值高限4ng／ml时，诊断敏感性为91．49％，诊断特异性为51．05％，当f／tPSA取临界值0．16时，诊断敏感性57．78％，诊断特异性为78．72％，当PSAD取临界值0．15时，诊断敏感性88．24％，诊断特异性为81．52％。结论PSA、f／tPSA和PSAD都是前列腺癌早期诊断穿刺或随访的指标，提高前列腺癌的诊断敏感性和特异性，其中PSAD较PSA和f／tPSA具有更高的诊断价值。

Objective To 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. Methods Retrospective 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） wasmeasured by transrectal ultrasound （TRUS）, and the fftPSA and PSAD values were calculated. The differ- ences of serum tPSA, fftPSA, 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 specific- ity. Results The 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. 01or P 〈 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%, diag- nostic specificity was 81.52%. Conclusions PSA, f/tPSA and PSAD are indicators for biopsy or follow- up 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.