Factors Analysis About Predicting The Probability Of Positive Initial Transrectal Ultrasound-guided Prostate Biopsy

Objective:To investigate the value of prostate specific antigen(PSA),DRE and MRI in predicting the probability of positive initial transrectal ultrasound-guided prostate biopsy?Method:The retrospective study was conducted in 820 patients who underwent initial transrectal ultrasound-guided prostate biopsy indications in Shandong university Qilu Hospital from January 2010 to December 2016.The clinical data was collected,including age,PSA,DRE and MRI.The 820 cases were divided into five groups by age:?50.51?60.61?70.71?80.>80,and divided into six groups according to the level of tPSA:0?4ng/ml.4?10ng/ml?10?20ng/ml?20?50ng/ml?50?100?>100ng/ml.The correlation between positive rate of prostate biopsy and age,PSA,DRE,MRI was analyzed.Result:The positive rate of prostate biopsy was 52.20%(430/820).The biopsy positive rate were rising increased with age(P<0.001).With the increase of tPSA,the positive rate of biopsy,the proportion of high-level PCa and the positive rate of ECT were rising(P<0.01).When the level of tPSA increased over 100ng/ml,the positive rate of prostate biopsy was 98.7%,the proportion of Gleason score?8 was 58.39%,and the positive rate of ECT was 71.53%.The positive rate of biopsy with positive and negative DRE were 67.52%and 40.32%.,the positive rate of biopsy of patient showed PCa in MRI was 72.89%,while 14.35%of patient didn't showed PCa in MRI,both of them had significant differences(P<0.001).The sensitivity of PSA>4ng/ml,PSA>10ng/ml,PSA>20ng/ml,DRE,MRI on screening PCa were 97.36%?87.02%?72.36%?60.94%?87.96%,the specificity were 11.40%.46.11%?77.20%?66.37%?60.59%,and the accuracy were 55.99%?67.33%?74.69%?63.47%?75.55%.Conclusion:Age,PSA,positive DRE and aberrant MRI are predictive factors of positive prostate biopsy.PSA as a screening indicator of PCa has high sensitivity and low specificity.Patients have a high risk of suffering from high levels of PCa and osseous metastasis with PSA>100 ng/ml.The sensitivity and specificity of DRE in the diagnosis of PCa is not high,MRI has a high sensitivity but low specificityin the diagnosis of PCa.