Poor standard mp-MRI and routine biopsy fail to precisely predict intraprostatic tumor localization

Area of Science:

• Urology
• Radiology
• Oncology

Background:

• Accurate prostate cancer localization is crucial for effective treatment planning.
• Focal therapy approaches necessitate precise identification of intraprostatic tumors.
• The role of non-PI-RADS assessed multiparametric MRI (mp-MRI) in tumor localization requires evaluation.

Purpose of the Study:

• To assess the localization accuracy of preoperative mp-MRI when not evaluated using the Prostate Imaging Reporting and Data System (PI-RADS) criteria.
• To compare the accuracy of non-PI-RADS mp-MRI with transrectal biopsies for prostate cancer localization.

Main Methods:

• Retrospective analysis of 106 patients undergoing radical retropubic prostatectomy with preoperative mp-MRI.
• Correlation of intraprostatic tumor locations identified by mp-MRI with subsequent biopsy and histopathology results.
• Evaluation of diagnostic performance metrics (sensitivity, specificity) for tumor localization.

Main Results:

• Non-PI-RADS mp-MRI demonstrated low sensitivity (25-62%) and variable specificity (60-94%) for tumor localization.
• Neither higher magnetic field strength nor endorectal coil use improved accuracy.
• No statistically significant concordance was found in any sextant; accuracy was not significantly better than chance.
• Transrectal biopsies showed comparable sensitivity (52-63%) but lower specificity (46-80%).

Conclusions:

• Routinely performed non-PI-RADS mp-MRI is inadequate for accurate prostate cancer localization.
• Transrectal biopsy also exhibits limitations in precise tumor detection.
• Accurate intraprostatic tumor detection, essential for focal therapy, mandates PI-RADS assessment by genitourinary radiologists.
• Non-PI-RADS prostate MRIs are not clinically justified due to lack of accuracy, patient discomfort, and cost.