Epidermoid Cyst of the Cerebellopontine Angle: A Case Report and Review of the Literature

Introduction: Epidermoid cysts of the cerebellopontine angle (CPA) are rare congenital lesions accounting for approximately 2% of primary intracranial tumors. Their insidious growth may cause significant neurological deficits due to mass effect on adjacent cranial nerves and brain structures. Case Presentation: We report a case of a 32-year-old woman referred for persistent headaches and balance disturbances. Initial MRI at an external institution raised suspicion of a CPA lesion. Confirmatory imaging at our facility showed a non-enhancing lesion with restricted diffusion in the left mesiotemporal region. The patient underwent combined frontotemporal and subtemporal craniectomy with amygdalohippocampectomy. Pathological examination confirmed an epidermoid cyst. Postoperative recovery was unremarkable. Discussion: MRI plays a pivotal role in diagnosing epidermoid cysts, especially diffusion-weighted imaging (DWI) and FLAIR sequences. Surgical resection is the mainstay of treatment, with total excision preferred but often limited by adherence to neurovascular structures. Subtotal resection followed by imaging surveillance remains a valid approach. Conclusion: CPA epidermoid cysts should be considered in the differential diagnosis of lesions in the posterior fossa or mesiotemporal area. Early diagnosis and individualized surgical planning are key for optimal outcomes.