Case of an Intracranial Malignant Peripheral Nerve Sheath Tumor in the Setting of Pacer-dependent Heart Block.

Intracranial malignant peripheral nerve sheath tumors (MPNSTs) are an extremely rare entity with only a handful of cases reported in the literature. MPNSTs typically occur in the extremities and the trunk. The treatment algorithm includes, when possible, gross-total resection as these tumors are extremely aggressive. When these tumors occur intracranially, they are termed malignant intracerebral nerve sheath tumors. The diagnosis hinges on immunohistochemistry and pathological features and often the diagnosis can be delayed for this reason. In this setting, it is critical to utilize intraoperative navigation, thus necessitating the use of fine-cut magnetic resonance imaging (MRI). This report presents a patient who presented with symptoms of obstructive hydrocephalus secondary to an intracranial mass. The patient underwent a full and extensive metastatic workup that was ultimately negative. To complicate things, the patient was fully pacemaker dependent. In this report, we review the literature surrounding this type of tumor, along with a detailed presentation of the case mentioned including the difficulties of cardiac pacing in the setting of MRI.