Prostate cancer remains the second-most common cause of cancer-related mortality among men, making accurate identification and treatment of clinically significant prostate cancer a priority. Prostate MRI has become an increasingly important component of the prostate cancer treatment paradigm, and has been repeatedly shown to improve the diagnostic accuracy of prostate biopsy in detecting clinically significant prostate cancer [[1], [2], [3], [4]]. Furthermore, routine use of MRI can help reduce overtreatment, reduce unnecessary biopsies, and increase the rate of detection of clinically-significant prostate cancer [5,6]. Although it has increasingly been adopted in prebiopsy decision making, the impact of prostate MRI on treatment and post-treatment outcomes is less clear. The association of MRI with grade concordance, prediction of extraprostatic extension (EPE), and development of biochemical recurrence (BCR) after radical prostatectomy (RP) has not been well-established.

Prostate MRI may impact grade concordance through performance of targeted biopsies for PI-RADS 3-5 lesions; in addition, grading the degree of extracapsular extension (ECE) on MRI could improve prediction of EPE at RP and BCR postoperatively. Existing models such as CAPRA, the Partin tables, and the Memorial Sloan Kettering Cancer Center (MSKCC) nomogram predict pathologic findings after RP, but their discrimination is moderate with none including MRI features [[7], [8], [9], [10], [11]]. Given increasing utilization of MRI before biopsy and for pretreatment decision making, we hypothesized that MRI may improve biopsy to RP grade group concordance and augment prediction of EPE and BCR after RP. Therefore, we performed a multi-institutional study to evaluate the association of preoperative MRI characteristics with pathologic findings at RP as well as risk of BCR after RP.