XXXX : features, detection, localization, and staging at endorectal MR imaging.

@entity5 @entity1 @entity263
PURPOSE: To retrospectively evaluate the accuracy of endorectal magnetic resonance (MR) imaging in the detection and local staging of transition zone @entity263 , with pathologic analysis serving as the reference standard, and to assess MR imaging features of these @entity5 . MATERIALS AND METHODS: The institutional review board approved this HIPAA-compliant retrospective study and waived the informed consent requirement. An institutional database of 986 @entity1 who underwent MR imaging before radical prostatectomy yielded 148 consecutive @entity1 with at least one transition zone @entity5 at step-section pathologic analysis. An additional 46 @entity1 without transition zone @entity5 were randomly selected as a control group. Two readers independently reviewed MR studies to identify @entity1 with transition zone @entity5 and determine the location and local extent of these @entity5 . Imaging features that helped in the identification of transition zone @entity5 were recorded. Descriptive and kappa statistics, as well as receiver operating characteristic and multivariate logistic regression analyses, were used. RESULTS: For identification of @entity1 with transition zone @entity5 , sensitivity and specificity were 75% and 87%, respectively, for reader 1 and 80% and 78%, respectively, for reader 2. Interreader agreement was fair. For detection of the location of transition zone @entity5 , the area under the receiver operating characteristic curve was 0.75 for reader 1 and 0.73 for reader 2. Interreader agreement was fair. The readers' accuracy in detecting transition zone @entity5 foci increased significantly (P=.001) as @entity5 volume increased. In the detection of extraprostatic extension of transition zone @entity5 , sensitivity and specificity were 56% and 94%, respectively, for reader 1 and 28% and 93%, respectively, for reader 2. Homogeneous low T2 signal intensity (P=.001 for reader 1, P<.001 for reader 2) and lenticular shape (P=.017 for reader 1) were significantly associated with the presence of transition zone @entity5 . CONCLUSION: MR imaging can be used to detect, localize, and stage transition zone @entity263 .
