Histopathologic Evaluation of Neurovascular Bundles and Periprostatic Tissue in Interfascial and Intrafascial Nerve-sparing Radical Prostatectomy Technique: A Cadaveric Anatomic Study

Abstract

To compare interfascial (IEF) or intrafascial (IAF) periprostatic nerve dissection technique in prostate tissue using immunohistochemical methods in fresh cadavers. Prostate tissues of 25 fresh cadavers were removed from rectum and other surrounding structures. IEF nerve dissection (n= 25) was performed on the right and IAF nerve (n= 25) dissection on the left side of each prostate under direct visualization. The base, center, and apex of each prostate lobes andfascia dissected were sampled for blind histopathologic evaluation. Total counts of nerve, artery, and vein were performed on hematoxylin and eosin stained sections, whereas sympathetic and parasympathetic nerve counts were performed on immunohistochemical stained sections. Iatrogenic surgical margin injury at base, center, and apex detected were compared between groups. Thickness of neurovascular bundle dissected in IAF was found significantly higher than IEF technique. The number of residual sympathetic fibers after dissection of neurovascular bundle was found significantly higher in IAF group. There were significant decreases in total nerve, parasympathetic, and sympathetic nerve counts only at the central region of prostate in IAF group. Asignificant decrease was found in the number of residual vein left in the fascia only at the apex by IAF dissection. Of surgical margin injury results, no significant difference was detected between IAF and IEF groups at any location. IAF provides better preservation of sympathetic but not parasympathetic fibers without increasing surgical injury of prostate capsule.