Introduction and objective: We aimed to report the clinical impact of preoperative multiparametric magnetic resonance imaging (mpMRI) concerning nerve sparing (NS) surgery in prostate cancer (PCa) patients, evaluating the appropriateness of mpMRI-induced surgical plan change.
Material and methods: 137 consecutive PCa patients were submitted to robot assisted radical prostatectomy (RARP) between January 2015 and February 2016 at two high-volume European centers. Before RARP, each patient was referred to 1.5-T mpMRI using endorectal coil or 3.0 T mpMRI. All patients underwent RARP by two experienced robotic surgeons using four-arm DaVinci Si or Xi Surgical System. NS approaches were classified on patient-based level as bilateral, unilateral or non–NS surgery. Indeed, the extent of neurovascular bundle (NVB) preservation was recorded on side-based level as Grade 1, Grade 2, Grade 3 and Grade 4 according to Tewari et al. classification. A preliminary surgical plan to determinate the extent of NS approach was recorded basing on clinical data. The final surgical plan was re-assessed after mp-MRI revision. The appropriateness of surgical plan change on side-based level was considered basing on the presence of ECE or positive surgical margins (PSMs) at level of NVBs area at final pathology.
Results: After revision of main clinical data and mpMRI results, 77 (56.2%), 34 (24.8%) and 26 (19%) patients were referred to bilateral, unilateral and non-NS approach, respectively. On side-based level, Grade 1, 2 and 3-4 NS was performed in 79 (28.8%), 108 (39.4%) and 87 (31.8%) sides, respectively. The overall PSMs rate was 12.4%. On patient-based (Table 1) and on side-based (Table 2) analysis, the mpMRI revision induced the main surgeon to change the NS surgical plan in 46.7% and 56.2% of cases, respectively. Indeed, the surgical plan change results equally assigned between the direction of less conservative and more conservative approach both on patient-based (54.7% vs. 54.3%) and on side-based levels (50% vs. 50%), resulting an overall appropriateness of 60% and 92.2%, respectively.
Conclusions: Mp-MRI could induce robotic surgeons to change the previous surgical plan in almost half of individuals. Since the appropriateness of surgical plan change influenced by mpMRI revision proved to be highest in case of switch towards highest grade of NVB preservation, mpMRI-guided NS surgery induced surgeon to preserve more neuronal tissue without increased risk of PSMs.