Surgical management of schwannomas in schwannomatosis: a comprehensive analysis of clinical outcomes and determinants of local recurrence.

Objective: Schwannomatosis is a rare genetic predisposition to develop multiple nonintradermal schwannomas affecting the spine and peripheral nerves, excluding vestibular schwannomas. Schwannomatosis-associated schwannomas can present with pain or motor deficits, prompting resection. In this study, the authors reported the clinical characteristics, surgical interventions, and postoperative outcomes of patients with schwannomatosis-related schwannomas treated with resection.

Methods: This was a retrospective cohort study of adult patients with schwannomatosis who had undergone resection of a symptomatic peripheral or spinal schwannoma at the authors' institution from September 2003 to June 2023. Data were extracted from electronic health records and provider notes.

Results: A cohort of 85 patients (57.6% women) had a mean follow-up of 68.4 ± 58.2 months after surgery. The mean age at the time of surgery was 44.6 ± 16.5 years. Pain was the most common presenting symptom (94.1%), followed by motor weakness (36.4%) and sensory deficits (32.9%). Just under two-thirds of the patients (64.7%) had undergone prior surgery for schwannoma, 20 (36.4%) of whom had a prior resection in the same exact location. Gross-total resection (GTR) was achieved in 88.2% of cases and en bloc resection in 69.4%. There were significant improvements in pain, motor weakness, and sensory deficits at the last postoperative follow-up visit. There was local tumor recurrence in 14 patients (16.5%), and the overall mortality rate was 4.7%. Univariate and multivariate analyses identified GTR as the strongest predictor of a decreased risk of local recurrence (HR 0.09, 95% CI 0.02-0.48, p = 0.005).

Conclusions: Patients with schwannomatosis commonly presented with neurological symptoms of pain, sensory deficits, or motor weakness associated with their schwannomas. Resection significantly improved their preoperative symptoms, and GTR was associated with a decreased risk of local recurrence.