Objective assessment of residual nerve tissues in radical prostatectomy specimens by immunohistochemical staining of neuronal nitric oxide synthase-positive nerves and its impact on postoperative erectile function

Urology. 2014 Dec;84(6):1395-401. doi: 10.1016/j.urology.2014.05.081.

Abstract

Objective: To compare the quality of surgical management of the neurovascular bundle (NVB) by assessment of neuronal nitric oxide synthase (nNOS)-positive nerves in surgical specimens between open retropubic radical prostatectomy (RP; ORRP) and robot-assisted RP (RARP).

Methods: This study included 65 (99 sides, NVB resection; 31 sides, NVB preservation) and 83 (106 sides, NVB resection; 60 sides, NVB preservation) patients undergoing ORRP and RARP, respectively. The posterior sectors from the apex, mid, and base areas on each side were immunohistochemically stained with an nNOS antibody.

Results: On the sides with NVB resection, there were no significant differences in the numbers of nNOS-positive nerves in any areas between the ORRP and RARP groups; however, on the sides with NVB preservation, the numbers of nNOS-positive nerves in the ORRP group were significantly higher than those in the RARP group at the apex (84.4 vs 59.2; P = .0028), mid (71.2 vs 52.4; P = .016), and base (148.0 vs 40.8; P <.001) areas. In 55 patients who were judged not to have severe erectile dysfunction before surgery and subsequently underwent nerve-sparing RP, there was a significantly inverse correlation between the total number of nNOS-positive nerves on both sides and the postoperative erectile function.

Conclusion: These findings suggest that RARP might be suitable for performing precise nerve-sparing surgery compared with ORPP, particularly in the base area of the prostate and that the quantification of nNOS-positive nerves in surgical specimens could be a useful approach for predicting the postoperative erectile function.

Publication types

  • Comparative Study
  • Evaluation Study

MeSH terms

  • Aged
  • Biopsy, Needle
  • Cohort Studies
  • Erectile Dysfunction / etiology*
  • Erectile Dysfunction / physiopathology
  • Follow-Up Studies
  • Humans
  • Immunohistochemistry
  • Male
  • Middle Aged
  • Nitric Oxide Synthase*
  • Postoperative Complications / diagnosis
  • Prostate / innervation*
  • Prostate / surgery
  • Prostatectomy / adverse effects
  • Prostatectomy / methods*
  • Prostatic Neoplasms / pathology
  • Prostatic Neoplasms / surgery*
  • Retrospective Studies
  • Risk Assessment
  • Robotics / methods*
  • Staining and Labeling
  • Surgery, Computer-Assisted / adverse effects
  • Surgery, Computer-Assisted / methods
  • Treatment Outcome

Substances

  • Nitric Oxide Synthase