Introduction: The rosette-forming glioneuronal tumor (RGNT) is a recently described, rare, and distinct tumor of the glioneuronal family. The presentation, natural history, and treatment response of these tumors is unclear given its rarity and absence of significant series with long-term follow-up.

Methods: We report 3 cases of young women admitted on symptoms of intracranial hypertension during the same period with infratentorial lesion and hydrocephaly. MRI showed a heterogenous tumor in the fourth ventricle or in the cerebellum mostly solid with a high signal on T2 sequence, low signal on T1 weighted imaging, focal hypointensities on T1 weighted imaging and on postcontrast series, intratumoral cysts with thick irregular rim enhancement. Treatment of these patients has consisted of subtotal or partial resection without adjuvant therapy.

Results: Histology revealed RGNT in the three cases. Except age and sex, no common factor was found.

Conclusions: Various unique imaging characteristics may allow for the preoperative identification of these tumors. Due to their benign nature and low propensity for recurrence, growth total resection should be aim when it’s possible. Radiotherapy may be considered for patients with tumor recurrence or in situation of inoperability.

Patient Care: Knowledge of RGNT evolution and improving of therapeutic management

Learning Objectives: to recognize clinical and radiological findings of RGNT

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