Diagnostic Value Of Biparameter Magnetic Resonance Imaging Of PI-RADS And PSA Related Indicators In First Prostate Biopsy

Objective:To evaluate the value of Prostate Imaging Reporting and Data System Version 2(PI-RADS)based biparametric Magnetic Resonance imaging(bp MRI)for predicting prostate biopsy results in patients with elevated prostate specific antigen(PSA).Methods:We retrospectively assessed the bp MRI from 539 patients who took transperineal template saturate biopsy from January 2015 to October 2017.The age,PSA level,free/total PSA,PSA density,prostate volume,and PI-RADS score of enrolled patients were analysed through univariate analysis and their difference was compared through chi-square test,t-test,and multivariate logistic regression analysis with SPSS to select the independent risk factors for prostate cancer(PCa)and clinically significant cancer(cs PCa).We also constructed the receiver operating characteristic curves to analyse the sensitivity and specificity of PI-RADS in prostate cancer(PCa)to explore the best cut-off value for the diagnostic of PCa and clinically significant cancer(cs PCa).Results:A total of 539 patients were included in our study among which 244 patients were positive and 295 patients were negative.In patients with positive results,59patients were diagnosed cs PCa.According to univariate analysis results,the age(P<0.001)and PI-RADS score(P<0.001)of the positive patient group were higher than the negative patient group,the difference was statistically significant;the age of the cs PCa group(P=0.023),PSAD(P=0.048)and PI-RADS scores(P<0.001)were higher than those of Ins PCa patients,f/t PSA(P=0.027)was lower than that of Ins PCa patients with statistically significant;multivariate logistic regression analysis demonstrated that f/t PSA(OR=2.283 P=0.049)and PI-RADS score(OR=9.046P<0.001)were independent risk factors for positive biopsy results,while PSAD(OR=4.54 P=0.038)and PI-RADS score(OR=8.254 P<0.001)are independent risk factor for cs PCa.The Yoden index analysis of multi-parameter at different thresholds for prostate cancer detection indicated that PI-RADS 3 is the optimal threshold for the diagnosis of PCa,PI-RADS 4 is the optimal threshold for the diagnosis of cs PCa.Based on the combination of the above factors,patients with a PI-RADS score of≤3and a PSAD of<0.15 ng/ml~2had the lowest cancer positive rate.Conclusions:PI-RADS score could be used to reduce the unnecessary prostate biopsies in patients with elevated PSA when combined with other PSA related indicators.Patients with a PI-RADS score of<3 and a f/t PSA ratio≥0.2 could avoid unnecessary biopsies.