MRI Displays the Prostatic Cancer Anatomy and Improves the Bundles Management Before Robot-Assisted Radical Prostatectomy

Objectives: To evaluate the impact of multiparametric magnetic0 resonance imaging (mpMRI) to guide the nerve-sparing (NS) surgical plan in prostate cancer (PCa) patients referred to robot-assisted radical prostatectomy (RARP).

Methods: One hundred thirty-seven consecutive PCa patients were submitted to RARP between September 2016 and February 2017 at two high-volume European centers. Before RARP, each patient was referred to 1.5T or 3T mpMRI. NS was recorded as Grade 1, Grade 2, Grade 3, and Grade 4 according to Tewari and colleagues classification. A preliminary surgical plan to determinate the extent of NS approach was recorded based on clinical data. The final surgical plan was reassessed after mpMRI revision. The appropriateness of surgical plan change was considered based on the presence of extracapsular extension or positive surgical margins (PSMs) at level of neurovascular bundles area at final pathology. Furthermore, we analyzed a control group during the same period of 166 PCa patients referred to RARP in both institutions without preoperative mpMRI to assess the impact of the use of mpMRI on the surgical margins.

Results: Considering 137 patients with preoperative mpMRI, the mpMRI revision induced the main surgeon to change the NS surgical plan in 46.7% of cases on patient-based and 56.2% on side-based analysis. The surgical plan change results equally assigned between the direction of more radical and less radical approach both on patient-based (54.7% vs 54.3%) and on side-based levels (50% vs 50%), resulting an overall appropriateness of 75%. Moreover, patients staged with mpMRI revealed significant lower overall PSMs compared with control group with no mpMRI (12.4% vs 24.1%; p ≤ 0.01).

Conclusions: mpMRI induces robotic surgeons to change the surgical plan in almost half of individuals, thus tailoring the NS approach, without compromising the oncologic outcomes. Compared to patients treated without mpMRI, the use of preoperative mpMRI can significantly reduce the overall PSMs.