Is vestibular schwannoma really a benign tumor? Case report and review.

Introduction: Vestibular schwannoma (VS) is a benign tumor that develops from Schwann cells of the eighth cranial pair, mainly in the cerebellopontine angle.

Case Presentation: We report the case of a 30-year-old female patient who developed left otalgia associated with neglected tinnitus, the evolution of which was marked by the development of a static cerebellar syndrome and a behavioral disorder, whose brain MRI revealed a locally advanced process in the cerebellopontine angle at the expense of the vestibulocochlear nerve, in favor of a VS, complicated by involvement of the tonsils, which unfortunately led to the patient's death.

Discussion: VS, formerly known as acoustic neuroma, is an extra-axial intracranial tumor that accounts for over 80% of pontocerebellar angle tumors, and is secondary in the majority of cases to inactivation of the neurofibromatosis type 2 (NF2) tumor suppressor gene, either by mutation of the NF2 gene or loss of chromosome 22q. In the majority of cases, it is unilateral and solitary, but in almost 8% of cases, it is associated with NF2. Cerebral MRI is the examination of choice for the detection, characterization, and diagnosis of VS without the need for biopsy, mainly with T1-weighted sequences before and after gadolinium injection. Treatment is based essentially on surgery or radiosurgery, depending on the size, impact, and expertise of the treatment team.

Conclusion: VS remains an important intracranial tumor entity, which can be life-threatening in cases of advanced local invasion.