Ge Gao MD, Presenter: Nothing to Disclose

Xiaoying Wang MD, Abstract Co-Author: Nothing to Disclose

Juan Hu, Abstract Co-Author: Nothing to Disclose

He Wang MD, Abstract Co-Author: Research Grant, General Electric Company

Xuedong Yang, Abstract Co-Author: Nothing to Disclose

To investigate the efficacy of multi-parametric(mp-MRI) in detection of prostate cancer(PCa) according to PI-RADS scoring system of ESUR prostate MR guideline 2012, and to find an appropriate combined mode of mp-MRI to improve the diagnostic efficacy of prostate cancer.

A total of 226 patients suspected of PCa by urologist were enrolled in the retrospective study, with permission of ethical committee. All patients received mp-MRI(T2WI, DWI, DCE, MRS) with subsequent ultrasound guided biopsy within 3 months. Two experienced radiologists, without known of the pathological diagnosis, graded the PI-RADS score of images of each sequence based on the 6 regions and patients. Inter-reader variability was assessed. The best weighting value of each sequence(T2WI, DWI, DCE, MRS) was calculated using FLDA. The fourfold table and the alternating free-response receiver operating characteristic(AFROC) method were used to analyze different modes of  combined application of T2WI score, DWI score, DCE score, MRS score, highest score, sum score, overall score and weighting score. Differences in the area under ROC curve(AUCs), sensitivity, specificty and accuracy were calculated at a statistical significance of P＜0.05.

This retrospective study proved that there was good inter-reader agreement with Kappa=0.830(6 regions)/0.739(patients). The weighting values obtained using FLDA were as follows: DWI＞T2WI＞MRS＞DCE. The AUCs of the combined modes based on patients were as follows: weighting score(0.955/0.952)＞overall score(0.923/0.917)＞sum score(0.922/0.913)＞highest score(0.867/0.859). The AUCs, sensitivity, specificity, PPV, NPV and accuracy of weighting score of both readers were 0.955/0.952, 93.94%/96.97%, 91.67%/85.71%, 91.18%/86.49%, 94.29%/96.77%, 92.75%/91.18% respectively.

PI-RADS scoring system, which is an effective assessment system for detection of PCa, could improve the PCa diagnosis. While different combined mode of mp-MRI have different diagnostic efficacy, especially the weighting score. The weighting values revealed that the most important sequences were DWI and T2WI, and more diagnostic information could be supplemented by MRS and DCE.

PI-RADS scoring system, which is a scoring system guidline for mp-MRI in detection of PCa, could improve the PCa diagnosis.

Gao, G, Wang, X, Hu, J, Wang, H, Yang, X, Retrospective Study of PI-RADS Scoring System: The Diagnostic Efficacy of Multi-parametric MRI in Detection of Prostate Cancer.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14009098.html