A Grading System for the Assessment of Risk of Extraprostatic Extension of Prostate Cancer at Multiparametric MRI

Abstract

To evaluate MRI features associated with pathologically defined extraprostatic extension (EPE) of prostate cancer and to propose an MRI grading system for pathologic EPE. Materials and Methods: In this prospective study, consecutive male study participants underwent preoperative 3.0-T MRI from June 2007 to March 2017 followed by robotic-assisted laparoscopic radical prostatectomy. An MRI-based EPE grading system was defined as follows: curvilinear contact length of 1.5 cm or capsular bulge and irregularity were grade 1, both features were grade 2, and frank capsular breach were grade 3. Multivariable logistic regression and decision curve analyses were performed to compare the MRI grade model and clinical parameters (prostate-specific antigen, Gleason score) for pathologic EPE prediction by using the area under the receiver operating characteristic curve (AUC) value. Results: Among 553 study participants, the mean age was 60 years 6 8 (standard deviation); the median prostate-specific antigen value was 6.3 ng/mL. A total of 125 of 553 (22%) participants had pathologic EPE at radical prostatectomy. Detection of pathologic EPE, defined as number of pathologic EPEs divided by number of participants with individual MRI features, was as follows: curvilinear contact length, 88 of 208 (42%); capsular bulge and irregularity, 78 of 175 (45%); and EPE visible at MRI, 37 of 56 (66%). For MRI, grades 1, 2, and 3 for detection of pathologic EPE were 18 of 74 (24%), 39 of 102 (38%), and 37 of 56 (66%), respectively. Clinical features plus the MRI-based EPE grading system (prostate-specific antigen, International Society of Urological Pathology stage, MRI grade) predicted pathologic EPE better than did MRI grade alone (AUC, 0.81 vs 0.77, respectively; P , .001). Conclusion: Higher MRI-based extraprostatic extension (EPE) grading categories were associated with a greater risk of pathologic EPE. Clinical features plus MRI grading had the highest diagnostic performance for prediction of pathologic EPE.

Prediction of biochemical recurrence in prostate cancer patients who underwent prostatectomy using routine clinical prostate multiparametric MRI and decipher genomic score

“…Relative lesion volume (MRI‐lesion‐percentage) was calculated as a ratio of MRI‐lesion‐volume and Prostate‐size. Presence of extracapsular extension (EPE‐MRI) was reported using a previously developed system, specifically: EPE‐MRI grade 0 = no suspicion for pathologic extracapsular extension (EPE); EPE‐MRI grade 1 = either curvilinear contact length or capsular irregularity and bulge; EPE‐MRI grade 2 = both curvilinear contact length and capsular irregularity and bulge; EPE‐MRI grade 3 = frank EPE visible at MRI or invasion of adjacent anatomic structures. Seminal vesicle invasion (SVI‐MRI) was reported as positive when there was a loss of the normal high signal within the seminal vesicles .…”

“…Presence of extracapsular extension (EPE‐MRI) was reported using a previously developed system, specifically: EPE‐MRI grade 0 = no suspicion for pathologic extracapsular extension (EPE); EPE‐MRI grade 1 = either curvilinear contact length or capsular irregularity and bulge; EPE‐MRI grade 2 = both curvilinear contact length and capsular irregularity and bulge; EPE‐MRI grade 3 = frank EPE visible at MRI or invasion of adjacent anatomic structures. Seminal vesicle invasion (SVI‐MRI) was reported as positive when there was a loss of the normal high signal within the seminal vesicles . In order to evaluate interreader variability, a randomly selected 20% of the final study cohort ( n = 18) was re‐reported using the same reporting system by the second reader, Reader B (S.L., 10 years of prostate MRI experience), blinded to the reports of Reader A.…”

“…Seminal vesicle invasion (SVI-MRI) was reported as positive when there was a loss of the normal high signal within the seminal vesicles. 16 In order to evaluate interreader variability, a randomly selected 20% of the final study cohort (n = 18) was rereported using the same reporting system by the second reader, Reader B (S.L., 10 years of prostate MRI experience), blinded to the reports of Reader A. The reporting scheme for Reader B are available: http://mrc.…”

Prostate-specific membrane antigen positron emission tomography (PSMA-PET) for local staging of Prostate Cancer: A Systematic Review and Meta-Analysis

“…Even more importantly, most of the studies did not de ne set criteria for assessing SVI and EPE regarding each of the components of PSMA-PET and MRI/CT, along with how to perform integrated interpretation of them. For MRI, several criteria for assessment of EPE (e.g., ESUR criteria, Mehralivand grading system, and length of tumor capsular contact) have been tested and validated in some studies [6,44,45]. Furthermore, recent efforts by multidisciplinary international group of experts, focused on proposing standardized assessment of PSMA-PET with the molecular imaging TNM system (miTNM, version 1.0) and PSMA reporting and data systems (PSMA-RADS) version 1.0; however, these systems have neither been tested nor validated in the literature [46,47].…”

“…Nomograms combining clinicopathological information including prostate-speci c antigen (PSA) levels, clinical stage based on digital rectal examination, and biopsy-related information (Gleason score, number and percentage of positive cores) are often used to predict the extent of prostate cancer [4]. However, there is an increasing number of studies showing that incorporating preoperative magnetic resonance imaging (MRI) results provide incremental value in predicting SVI and EPE [4][5][6][7]. Nevertheless, these results are still imperfect with area under the curves (AUC) ranging from 0.74-0.87 [8][9][10].…”