Rosette-forming glioneuronal tumor (RGNT) of the fourth ventricle: Case report and review of literature.

Rosette-forming glioneuronal tumor (RGNT) of the fourth ventricle has been identified as a novel and distinctive type of primary central nervous system neoplasm. In this report, we present a case with RGNT arising from the right cerebellar hemisphere. A 30-year-old female patient complained of headache for a five-year duration. Preoperative MRI revealed a well-circumscribed, cystic-solid lesion with hypo-intensity on T1-weighted image, hyper-intensity on T2-weighted image, and significant dot-like enhancement after IV contrast. Gross total resection was achieved in this case via suboccipital retro-sigmoidal approach, and RGNT was confirmed in the final histopathological diagnosis. RGNT of the fourth ventricle is a rare, benign tumor with an excellent prognosis. Operation is recommended as the prior protocol of treatment, and the follow-up MRI is necessary to evaluate the long-term prognostic effects. Currently, only one case of progression or recurrence has been reported in the postoperative course.