Revisiting the Concept of Nerve-Sparing Radical Hysterectomy: A Proof-of-Concept Prospective Study From a Cervical Cancer Cohort.

BACKGROUND: Nerve-sparing radical hysterectomy aims to preserve the autonomic innervation of pelvic organs. In most studies, the preservation of the parasympathetic component of pelvic innervation is achieved by sparing the lymphovascular-neural tissue located at the base of the lateral paracervical tissue. This study explores an alternative surgical technique based on a different anatomical pathway of parasympathetic fibers, running more cranially and deeply within the pararectal space.

METHODS: This was a prospective proof-of-concept cohort study in six patients with stage IB2-IIA cervical cancer undergoing nerve-sparing radical hysterectomy with intraoperative neurophysiological monitoring (IONM). A multimodal IONM protocol was employed, including electrical stimulation, triggered electromyography, and cystometry, to identify and assess key parasympathetic nerve pathways.

RESULTS: The newly identified alternative pathway of putative parasympathetic fibers was consistently observed intraoperatively in this small cohort. Real-time neurophysiological monitoring suggested that these fibers may contribute to parasympathetic control of bladder and rectal function. Notably, preserving these fibers did not require complex dissection. All patients maintained normal pelvic organ function with no perioperative complications or postoperative dysfunction.

CONCLUSIONS: This pilot study provides evidence that the putative parasympathetic fibers essential for bladder and rectal function run cranially within the pararectal space, rather than through the posterolateral paracervical tissue. Optimizing neurophysiological parameters for IONM and selectively preserving the deeper fiber pathway may offer a safer and more effective approach to nerve-sparing radical hysterectomy. Our data would be useful in informing future larger comparative trials.