Surgical Outcomes of Retroperitoneal and Pelvic Schwannomas/Neurofibromas

Overview

This study evaluates the safety, feasibility, and outcomes of surgical resection of retroperitoneal and pelvic schwannomas and neurofibromas using intraoperative electrophysiological monitoring. It highlights the importance of multidisciplinary planning and tailored surgical approaches based on tumor characteristics and location.

Background

Benign peripheral nerve sheath tumors, including schwannomas and neurofibromas, can arise along various nerves but rarely occur in the retroperitoneal and pelvic regions. These tumors are typically slow growing, well-circumscribed, and benign, often presenting with nonspecific symptoms related to mass effect. Imaging modalities such as CT and MRI assist in tumor localization but cannot definitively diagnose schwannomas, necessitating tissue biopsy for confirmation. Complete surgical excision remains the gold standard treatment, though proximity to major vessels and neural plexuses complicates resection.

Data Highlights

The retrospective study included patients treated surgically for retroperitoneal and pelvic schwannomas/neurofibromas between 2015 and 2024 at University Hospital Göttingen. Preoperative imaging with contrast-enhanced CT angiography and MRI was performed for all patients. Intraoperative electrophysiological monitoring (MEPs and EMG) was employed in all cases. Preoperative ureteral stenting was used to minimize ureteral injury. Surgical approaches included midline laparotomy, Pfannenstiel incision, and trans-retroperitoneal approach depending on tumor size and location. Seven recent cases included CT-guided core-needle biopsy for diagnosis confirmation.

Key Findings

• Retroperitoneal and pelvic schwannomas/neurofibromas are rare, comprising about 10% of retroperitoneal tumors and 1–3% of schwannomas overall.
• Preoperative imaging alone is insufficient for definitive diagnosis; CT-guided biopsy improves diagnostic accuracy and surgical planning.
• Intraoperative electrophysiological monitoring facilitates nerve-sparing resections and enhances surgical safety.
• Multidisciplinary tumor board discussions optimize individualized surgical strategies and risk assessment.
• Complete surgical excision via tailored approaches (transperitoneal or retroperitoneal) is typically curative with low recurrence rates.
• Preoperative ureteral stenting reduces risk of ureteral injury during tumor dissection.

Clinical Implications

Clinicians should consider preoperative biopsy to confirm benign schwannoma pathology, enabling conservative, nerve-sparing resections. Employing intraoperative electrophysiological monitoring can improve functional outcomes by preserving neural structures. Multidisciplinary collaboration is essential for planning complex resections near critical vascular and neural anatomy. Preoperative ureteral stenting is recommended to minimize ureteral injury risk.

Conclusion

Surgical resection of retroperitoneal and pelvic schwannomas/neurofibromas using intraoperative electrophysiological monitoring is safe and effective. Individualized, multidisciplinary approaches optimize outcomes and preserve neurological function.

References

1. Neurosurgical Patient Population Study 2015-2024 -- Surgical Approaches and Outcomes for Resection of Retroperitoneal and Pelvic Schwannomas/Neurofibromas