Vestibular schwannoma: predictive factors of long-term postoperative neurological outcome

Introduction: Vestibular schwannoma (VS) is a slow-growing, benign tumor that is usually diagnosed when symptoms develop. Surgical management aims to reduce long-term sequelae (LTS) associated with late diagnosis.Objective: Identify predictive factors of LTS after VS surgery and clinical outcome measured by modified Rankin scale (mRS).Methods: This cohort study included patients submitted to VS surgery from 1999 to 2014, with a mean follow-up of 6.4 ± 4.5 years. Disability was assessed across the mRS the primary outcome was defined by scores 3 to 6, which implied poor outcome in neurological recovery. Predictive factors were identified through multivariate logistic regression.Results: A total of 101 patients were included in this study. Fifty-one (50.49%) presented mRS ≥ 3 on the late postoperative period. Men comprise 22.8%, and the mean age was 47.1 ± 16.0 years (range19-80). Patients with mRS ≥ 3 presented larger tumors (3.7 ± 1.1 cm vs. 3.2 ± 1.0 cm, p < .001), less total resection (50% vs. 76.7%, p < .010) and more neurofibromatosis II(NFII) (84.9% vs. 64.3%, p = .023). On multivariate analysis NFII, tumor size and type resection were predictive of degree of autonomy (mRS ≥3: NF II (OR 3.5, 95% CI 1.08-11.36, p = .036) and tumor size (each 1 cm, OR1.51, 95% CI 0.96-2.38, p = .050).Conclusion: Tumor size, presence of NFT II, type of surgical approach and number of surgeries were identified as predictive factors of functional sequelae in long-term follow-up after VS surgery.HighlightsOne-third of our patients presented some degree of disability that impact in autonomy (mRS ≥ 3) in the late postoperative period.Tumor size, NFII, surgical approach were predictive to comprise independency.Considering the cranial nerve monitoring and late diagnosis, our results can give some contribution to understanding the Brazilian profile of VS surgery.Our findings suggests the need to look over what it is well recognized and identify aspects that affect the prognosis such as functional disabilities in VS surgery.