Periprostatic distribution of nerves in specimens from non-nerve-sparing radical retropubic prostatectomy

Abstract

OBJECTIVES: To investigate the distributive pattern of nerves surrounding the prostate by analyzing specimens from non-nerve-sparing radical retropubic prostatectomy (RRP). METHODS: We histologically analyzed specimens from 95 cases of non-nerve-sparing RRPs performed at our institution by examining 12 representative slides from each case. We reconstructed images from scanning the slides and prepared them for analysis by placing them on a circle divided into 12 designated zones. The number of total nerves and ganglionated nerves on the outside of the prostatic capsule was determined manually for each zone. We assessed the locations of ganglionated nerves separately, and also assessed the localization of vessels and nerve trunks in the posterolateral region of the prostate along with the actual shape of the neurovascular bundle (NVB). RESULTS: Significant proportions (19.9%-22.8%) of total nerves counted were located on the anterior side of the prostate. Ganglionated nerves, present in posterolateral sectors in all cases, were also located on the anterior side of the prostate in some cases (21.1%). We observed NVB in a relatively round, bundle-like formation in 51.6%, whereas NVB was more spread anteriorly, rather than having a rounded structure, in 48.4%. CONCLUSIONS: Anatomic variation exists regarding the periprostatic distribution of nerves, including the formation of NVB. We observed a significant proportion of periprostatic nerves, particularly ganglionated nerves, on the anterior side of the prostate. Thus, further investigation is needed regarding the actual role of these observed nerves not included in NVB.