Evaluation Of The Performance Of Ultrasound Elastography Combined With PI-RADS For Malignancy Risk Stratification In Prostate Lesions

PURPOSE: This study retrospectively evaluated the prognostic performance of elastography Q-analysis score(EQS)combined with the Prostate Imaging Reporting and Data System(PI-RADS)for malignancy risk stratification in prostate lesions based on transrectal ultrasound(TRUS)-magnetic resonance imaging(MRI)fusion image.MATERIALS AND METHODS: between October 2017 and October 2018 in our hospital and who met the inclusion criteria were retrospectively evaluated.The performance of EQS and PI-RADS was evaluated by subjects' receiver operating characteristic(ROC)in differentiating malignant and benign prostate nodules.The combination methods(“tandem”;“parallel”)of EQS and PI-RADS for malignancy risk stratification in prostate lesionsRESULTS:A total of 62 prostate lesions in 62 patients were included.ALL of then underwent biopsy,29 patients were prostate cancer,the rest were benign prostate lesion.Both EQS and PI-RADS were significantly higher in malignant lesions than benign lesions.By calculating ROC curve according to EQS,when EQS cut-off value at 2.05,the sensitivity,specificity,AUC,PLR,NLR,PPV,NPV and Youden's index of prostate cancer diagnostic came as 86.2%?81.8%?85.9%?4.73?0.169?80.6%?87.1%?68%respectively.By calculating ROC curve according to PI-RADS,when PI-RADS cut-off value at 4,the sensitivity,specificity,AUC,PLR,NLR,PPV,NPV and Youden's index of prostate cancer diagnostic came as 82.7%?69.7%?84.2%?2.72?0.25?70.6%?82.1%?52.4% respectively.When EQS and PI-RADS were “tandem”,a higher level of diagnostic specificity(87.9%),PLR(6.55)and PPV(85.1%)were achieved.When EQS and PI-RADS were “parallel”,a higher level of diagnostic sensitivity(96.5%),NLR(0.06)and NPV(95.2%)were achieved.CONCLUSIONS:Both EQS and PI-RADS had good diagnostic performance in differentiating malignant and benign prostate cancer.The combination of EQS and PI-RADS improved the diagnostic performance at a certain degree.The “parallel” method had a higher level of diagnostic sensitivity(96.5%),NLR(0.06)and NPV(95.2%)compared with the two methods used alone.According to this conclusion,using “parallel”method in prostate cancer diagnostic can avoid unnecessary surgery and biopsy.Specially,if both EQS and PI-RADS are negative,meaning the “parallel” result is negative,regular follow-up are suggested.In addition,the “tandem” method had a higher level of diagnostic specificity(87.9%),PLR(6.55)and PPV(85.1%)compared with the two methods used alone.If the “tandem” result shows positive,which means both EQS and PI-RADS are positive,a higher risk level of malignant prostate cancer is considered and further diagnosis and treatment will be suggested.