Comparison The Diagnostic Value And Application Of PSA Parameters For Prostate Cancer In Gray Zone

Objective:When PSA level is in the gray zone,it is difficult to diagnose prostate cancer.The parameters of PSA are used to diagnose when in the gray zone.The purpose of this study is to compare and evaluate the diagnostic value of each parameter in the gray zone for PCa,and to improve the detection rate of PCa in the gray zone.Method:We used a retrospective study about patients who underwent the first transrectal prostate biopsy in the First Affiliated Hospital of Soochow University from January 2016 to December 2018.Collect PSA parameters including PSA mass,PSA mass ratio,f/t,PSA density and(f/t)/PSAD.Patients were classified into BPH group and PCa group according to the pathological results of the biopsy.The diagnostic value of each parameter was described and compared by ROC curve.Secondly,64 PCa patients who underwent radical prostatectomy in our hospital were classified into three groups according to the severity of PCa.The correlation between each parameter and the severity of prostate cancer was compared.Results:(1)The AUC of each parameter was sorted as PSAMR(0.845)>PSAD(0.814)>(f/t)/PSAD(0.814)>(f/t)>(f/t)/PSAD(0.732)>f/t(0.617)>PSAM(0.617)>PSAM(0.555);the largest youden index of each parameter was sorted as PSAMR(0.532)>PSAD(0.427)>(f/t)/PSAD(0.375)f/PSAD(0.375)>f/t(0.223)>PSAM(0.223)>PSAM(0.149);the reference cut-off piont of each parameters were PSAD(0.12)(f/t)/PSAD(0.72),f/t(0.13),PSAM(14.27),respectively.(2)when they are under the reference cut-off point,PSAMR and PSAD had the highest positive biopsy rate,while(f/t)/PSAD had the lowest misbiopsy rate,as well as the highest biopsy avoidance rate and biopsy accuracy.(3)When combined MRI and PSAMR,The AUC,sensitivity,specificity,and maximum Youden index was 0.947,97.1%,73.6%,0.707 respectively.(4)f/t and(f/t)/PSAD were negative correlated with the severity of PCa,while PSAD and PSAM were positive correlated with the sevirty of PCa.and the correlation was PSAMR>PSAD>(f/t)/PSAD>f/t.Of note,PSAM had no significance in assessing the risk of prostate cancer.Conclusions:(1)Among the relevant parameters of PSA,except PSAM,the other parameters have a certain diagnostic value in gray zone.The rank of diagnostic value is PSAMR>PSAD>(f/t)/PSAD>f/t.(2)No matter how it changes,the parameters of PSA are always derivatives of PSA,which has its own limitation.Furthermore,combining with the MRI can improve the diagnostic rate of PCa.(3)PSA parameters may also be related to the severity of PCa in gray zone.PSAMR and PSAD are positive correlated with the severity of PCa,whereas f/t and(f/t)/PSAD are negative correlated with the severity of PCa.Particularly,PSAMR is most correlated.