Disseminated Rosette-Forming Glioneuronal Tumor with Spinal Drop Metastasis, a Uniquely Aggressive Presentation of Rare Tumor.

Abstract

The rosette-forming glioneuronal tumor (RGNT) is a rare World Health Organization grade I tumor, most often originating in the fourth ventricle and characterized by a predominant glial component, as well as a neurocytic component. Despite its benign grading, there are a few documented cases of RGNT displaying more aggressive behavior with malignant characteristics. Herein, we describe a uniquely aggressive presentation of RGNT in a 49-year-old man initially presenting with obstructive hydrocephalus with lesions in the right frontal lobe, fourth ventricle, and left lateral ventricle. The patient was found to have 2 distinct intracranial entities: a right frontal meningioma and disseminated intraventricular RGNT. He underwent an anatomically limited resection of the fourth ventricular lesion with fourth ventricle-to-subarachnoid space shunting. His disease progressed thereafter, with diffuse intracranial dissemination and drop metastases in the lumbar spine. He was treated with craniospinal radiation and remains on palliative care 5 months after completion of radiotherapy. This case supplements and complements the handful of published cases available documenting the evolution of a particularly aggressive case of disseminated RGNT.