The Application Of Prostate-specific Antigen And Its Derivatives In The Prediction Of Prostate Cancer

Objective: value the application of TPSA(Total prostate-specific antigen), fPSA / TPSA(Percent free prostate-specific antigen), MRI-based PV(Magnetic Resonance Image calculated on prostate volume), MRI-based PSAD(prostate specific antigen density) with a PSA of 4.0–10.0 ng ml-1 and 10.1–20.0 ng ml-1, in order to improve the diagnosis of prostate cancer, and reduce unnecessary prostate biopsy.Materials and methods: a total of 91 patients who suffered from transrectal prostate biopsy between January 1, 2015 to 31 December 2015 at Xie He Hospital which was affiliated to Fujian Medical University,was analyzed( 49 patients with a serum TPSA of 4.0–10.0 ng ml-1 and 42 patients with a serum TPSA of 10.1–20.0 ng ml-1). The information of the patients’ age, TPSA, fPSA / TPSA, prostate volume(MRI-based PV), MRI-based PSAD and the results of prostate biopsy was collected. Analyze the differences among these factors by the means of Statistics. And ROC curve(receiver operating curve-specific) was used to compare the diagnostic value of each factors of prostate cancer. Moreover, multivariate logistic regression analysis was used to assess the most effective diagnostic factor of prostate cancer.Results: In this study, 91 patients underwent transrectal ultrasound-guided prostate biopsy. The biopsy results showed that 30 patients had prostate carcinoma with a PSA of 4.0–20.0 ng ml-1. The positive rate of diagnosis was 33.0%(30/91).Among them, there were 49 patients underwent transrectal ultrasound-guided prostate biopsy with a PSA of 4.0–10.0 ng ml-1. And 13 of them were diagnosed prostate cancer. The positive rate of diagnosis was 26.5%(13/49); While 17 patients were diagnosed prostate cancer with a PSA of 10.1–20.0 ng ml-1. The positive rate of diagnosis was 40.5%(17/42). Mann-Whiteny U test was used to compare the differences of each factor with a PSA of 4.0–10.0 ng ml-1 and 10.1–20.0 ng ml-1. When the serum TPSA ranged from 4ng / ml to 20 ng / ml, the factors of PV and PSAD were statistically significant(P<0.05). When the serum TPSA ranged from 4ng / ml to 10 ng / ml, the factors of %fPSA,PV and PSAD were statistically significant(P<0.05); While the factors of PV and PSAD were statistically significant(P<0.05) with a PSA of 10.1–20.0 ng ml-1. Then,we used ROC curves to analyse the value of predicting prostate cancer among these factors. When TPSA between 4-20 ng ml-1, area under the ROC curve of PV and PSAD were 0.708,0760, respectively; when TPSA between 4-10 ng ml-1, area under the ROC curve of %fPSA, PV and PSAD were 0.704,0.759,0.746, respectively; when TPSA between 10-20 ng ml-1, area under the ROC curve of PV, PSAD were 0.711,0746, respectively. Furthermore, multivariate logistic regression analysis was used for those factors which had significant difference. The result showed that only PSAD was statistically significant(P<0.05).Conclusion: With a PSA of 4-10 ng ml-1,% fPSA, PV and PSAD are effective to predict prostate biopsy outcome. And with a PSA of 10-20 ng ml-1, PV and PSAD are both effective to predict prostate biopsy outcome. Among them,PSAD is the most effective diagnostic factor of prostate cancer.