Applied research of prostate specific antigen combined with prostate cancer gene 3 in diagnosis of prostate disease

Objective To detect the expression of peripheral blood free prostate specific antigen (fSPA) , total prostate specific antigen (tSPA) , prostate specific antigen density (PSAD) and prostate cancer gene 3 (PCA3) in prostate disease, and the significance of combined detection of fSPA, tSPA and PCA3. Methods 67 patients with prostate cancer, 75 patients with prostatic hyperplasia and 70 healthy male were selected as the research objects from Dec. 2014 to Jul. 2016. The serum level of fSPA and tSPA was detected by chemiluminescence immune staining method. The prostate volume was tested by ultrasonic sound and PSAD value was calculated. The total RNA was extracted by Trizol, and the serum PCA3 mRNA expression was detected by RT-PCR. The specificity and sensitivity of combined detection of fSPA, tSPA and PCA3 were analyzed. Results The serum levels of fSPA, tSPA, PSAD and PCA3 in prostate cancer were significantly higher than those in patients with prostatic hyperplasia and healthy male, and they were higher in patients with hyperplasia of prostate than in healthy male, and the differences had statistical significance (P<0.01) . The serum levels of fSPA, tSPA, PSAD and PCA3 were higher in patients with Gleason score ≥7 points and in T3-T4 stage than in patients with Gleason score <7 and in T1-T2 stage, and the difference had statistical significance (P<0.01) . The serum levels of fSPA, tSPA, PSAD and PCA3 were positively correlated with Gleason score and TMN pathological stage, and the difference had statistical significance (P<0.01) . The AUC value of fSPA, tSPA, PSAD and PCA3 in diagnosis of prostate cancer was 0.53, 0.57, 0.63 and 0.75, and the AUC value of combined detection was 0.92. The combined detection efficiency was higher than the single index.The specificity of fSPA, tSPA, PSAD and PCA3 was 67.16%, 68.66%, 73.13% and 85.07%, and the sensitivity was 71.64%, 70.15%, 74.63% and 82.09% respectively. The specificity of combined detection was 97.01%, the sensitivity was 92.54%, and the difference had statistical significance (P<0.01) . Conclusion The serum level of fSPA, tSPA, PSAD and PCA3 is increased in prostate disease, and is negatively correlated with Gleason score and TMN pathological stage. The combined detection of fSPA, tSPA, PSAD and PCA3 can improve the sensitivity and specificity of prostate disease diagnosis, and is of high clinical value. Key words: Prostate disease; Prostate specific antigen; Prostate specific antigen density; Prostate cancer gene 3