BRAF-Mutated Pleomorphic Xanthoastrocytoma of the Spinal Cord with Eventual Anaplastic Transformation

Background Pleomorphic xanthoastrocytoma (PXA) is an uncommon, primary neoplasm of the central nervous system with a relatively favorable prognosis. Most patients are managed with surgery alone and experience significant long-term survival. PXAs occur most commonly along the superficial surfaces of the temporal lobes. Although these tumors may occur in other regions of the brain, their origin within the spinal cord is rare, and it is unclear whether spinal cord PXAs should be managed differently from their intracranial counterparts. Case Description We describe a 31-year-old patient with a PXA of spinal cord origin who despite surgery, radiation, and multiple chemotherapy regimens experienced anaplastic transformation of his tumor and died of extensive leptomeningeal progression. Conclusions To our knowledge, our patient represents the seventh reported case of PXA of the spinal cord but is the first described to have a BRAF mutation. Specifically, both the initial and recurrent tumors of the patient showed the same BRAF V600E mutation, which refutes previous suggestions that BRAF mutations may be limited to intracranial PXAs and also shows that BRAF mutations may occur earlier in PXA tumorigenesis.