Background: Distinguishing between organ-confined disease and extraprostatic extension (EPE) is crucial for the treatment of patients with prostate cancer. EPE is associated with an increased risk of biochemical recurrence, positive surgical margins, and metastatic disease. An MRI-based EPE scoring system was developed by Mehralivand in 2019; however, it has not been adopted in the Urology community. The purpose of this study is to evaluate the association of MRI-based EPE scoring with the pathologic EPE (pEPE) after radical prostatectomy. Methods: We conducted a retrospective review on a prospectively collected database of male patients who underwent a prostate MRI with EPE scoring by a trained genitourinary radiologist and subsequent robotic radical prostatectomy at our institution from September 2020 to December 2022. The associations between MRI EPE (mEPE) score and the presence of EPE on surgical pathology (pEPE) were examined using multivariable logistic regression. Results: A total of 194 patients met inclusion criteria with a median age of 63 years and prostate specific antigen (PSA) 7 ng/mL. Among those with mEPE score 3, 96% had pEPE. Those patients with an mEPE score ≥2 had an increased risk of pEPE compared with those with mEPE score 0 (odds ratio 3.79; 95% confidence interval 1.28-11.3) Furthermore, those with an mEPE score 3 were significantly more likely to have pEPE compared with those with mEPE score 0, 1 and 2 independently. Conclusion: MRI EPE is a straightforward tool that strongly correlates with the presence of pEPE. If validated prospectively, this scoring system could assist in counseling patients regarding nerve-sparing approach.
Keywords: pathology; prostate cancer; radiology.