Thoracic spine intra- and extradural dumbbell-shaped meningioma: Case report and extensive review of the literature with 21 cases

Introduction: Spinal dumbbell-shaped meningioma is a rare condition usually mistaken preoperatively for schwannoma. The present study reported a case of dumbbell-shaped meningioma, with an extensive review of literature.

Methods: A documented case of thoracic spine dumbbell-shaped meningioma is reported, followed by an extensive review of the literature to analyze epidemiological features, pathogenesis, histopathological diagnosis, location, Eden classification, surgical treatment and outcome in such tumors.

Results: Case report: A 55 year-old woman was admitted with paraparesis and paresthesia of lower limbs. MRI showed a dumbbell-shaped meningioma of the thoracic spine. The tumor was totally removed via a posterolateral approach.

Review of the literature: Twenty-one spinal dumbbell-shaped meningiomas were reported in the last twenty years (1997-2017). Mean patient age was 46.57 years, with female predominance. Mean disease progression was 23.11 months. The thoracic spine was the predominant site (38.09%), followed by the cervical spine (33.33%). Eden type-3 was the most frequent tumor type, accounting for 66.67% of cases. In all cases, meningiomas were classified as WHO grade I. Complete removal (Simpson I-II) was achieved in 75% of cases. There was recurrence in 3 patients (14%), including 1 case of malignant transformation leading to death at 12 years post-surgery.

Conclusion: Spinal dumbbell-shaped meningioma is mainly of the benign subtype. Long-term follow-up shows low rates of morbidity and mortality.