Intraventricular WHO Grade 3 Pleomorphic Xanthoastrocytoma: A Rare Case Report and Review of the Literature.

Cerebral pleomorphic xanthoastrocytoma (PXA) in patients with Neurofibromatosis Type 1 (NF1) is truly a rare entity. Intraventricular anaplastic PXA (APXA) is an even more uncommon presentation, with only three cases reported in the literature. We present the case of a 30-year-old female with known NF1 who developed an intraventricular WHO Grade 3 PXA. The tumor was initially resected but recurred aggressively, requiring further surgery and adjuvant therapy with radiation, lomustine, and bevacizumab. Despite treatment, the tumor continued to progress, and the patient's clinical course deteriorated. Distinguishing Grade 3 PXA from epithelioid glioblastoma can be diagnostically challenging and often requires further molecular testing. Aggressive multimodal therapy including maximal safe resection, radiation, and chemotherapy may be warranted, but outcomes remain poor. The challenging location of this patient's tumor in the ventricular system added to the complexity of overall treatment. Furthermore, the association of WHO Grade 3 PXA with NF1 is exceedingly rare, and the optimal management and prognosis of this rare tumor in the setting of NF1 are not well established. This case report highlights the unique challenges in diagnosing and managing intraventricular WHO Grade 3 PXA, particularly in the context of NF1. Additional research is necessary to enhance the understanding and effective management of these rare and aggressive tumors.