PSA、PSAD、f／tPSA在早期前列腺癌诊断作用的研究

目的探讨前列腺特异性抗原（PSA）、PSA密度（VSXO）、游离PSA／总PSA比值（f／tPSA）在诊断早期前列腺癌（PCa）中的价值。方法对640例患者行前列腺穿刺活检，其中PSA〈4．0ng／ml者36例为直肠指诊及直肠超声可疑者。病理诊断为415例良性前列腺增生和225例前列腺癌，利用酶联免疫法（ELISA）测定患者血清中的PSA、游离PSA（fPSA），利用经直肠超声测定前列腺体积，并计算出f／tPSA及PSAD进行统计学分析。结果PCa组患者血清的PSA、PSAD明显高于前列腺良性增生（BPH）组（P〈0．01），f／tPSA明显低于BPH组（P〈0．01），但当血清PSA为4—20ng/ml时，两组患者PSA没有明显差异（P〉0．05）。以PSA〉4．0ng／ml、PSAD〉0．15、f／tPSA〈0．18为临界值可明显提高对PCa诊断的特异性，特别是当血清PSA为4—20ng／ml时对提高临床诊断更有意义。结论联合测定PSA、fPSA并计算f／tPSA及PSAD对诊断PCa具有明显临床意义。

The roles of PSA, PSAD, f/tPSA hi early diagnosis of prostate cancer

Objective To study the early diagnostic value of prostate-specific antigen （PSA）, density of PSA（PSAD） ,free/total prostate-specific antigen ratio（f/tPSA） for prostate cancer. Methods prostate biopsy was performed in 640 subjects;among them, 36 subjects had PSA 〈 4.0 ng/ml and positive findings for digital rectal examination and tramrectal ultrasound,which were suspicious of cancer. The patients with bisectional prostate hypertrophy（ BLIP,415 cases） and prostate cancer （PCa,225 cases） were diagnosed by pathobiology, and whose levels of PSA, and fPSA were examined in sertms by ELISA.The volume of prostate were examined by tran- srectal ultrasound, The associations of PSA, PSAD and f/tPSA with the prostate biopsy results were analyzed. Results PSA and PSAD levels in serum of patients with PCa was higher than BPH,f/tPSA was lower,they have statistics difference between PCa and BPH（ P 〈0.001） ,but in the subjects with PSA 〈 4.0ng/ml PSA had no significant difference （ P 〉 0.05） between patients with prostate cancer and patients with BPH. Conclusion The clinical application of f/t PSA ratio and PSAD can improve diagnosis of prostate