Seizure Presentation of a Grade II Astrocytoma in a Patient With Ollier's Disease: A Case Report and Brief Review.

Ollier's disease (enchondromatosis) is a dysplasia of cartilage characterized by multiple enchondromas. Current evidence supports a measurable prevalence of concurrent gliomas in patients with Ollier's disease. In patients with Ollier's disease, isocitrate dehydrogenase 1 (IDH1) and isocitrate dehydrogenase 2 (IDH2) mutations were shown to be a predisposing factor to the development of astrocytomas in conjunction with subsequent mutations in adenosine triphosphate (ATP)-dependent helicase ATRX (ATRX) and tumor protein p53 (TP53). We present the case report of a 21-year-old man with an adolescent diagnosis of Ollier's disease who developed a grade II astrocytoma in early adulthood. The patient presented to the emergency room with seizures, was given anti-seizure medication, and later underwent chemotherapy and resection of the astrocytomas. A literature review showed 12 additional patients diagnosed with Ollier's disease who were subsequently diagnosed with a grade II astrocytoma later in life. After reviewing the genetics behind Ollier's disease, the importance of performing routine cranial magnetic resonance imaging (MRI) in these patients becomes apparent.