Abstract
Oligoastrocytoma (OA) is an extremely rare tumor that may be difficult to diagnose, as it mimics multiple sclerosis (MS) clinically and radiologically. OA and MS are both space-occupying lesions. The symptoms of OA are complex and depend on tumor location and size. The clinical symptoms of OA are frequently not typical of glioma; therefore, OA is associated with a high misdiagnosis rate. We herein share our experience with diagnosing a rare OA case with atypical symptoms, which was initially diagnosed as MS, while stereotactic biopsy provided the final diagnosis. Due to the rarity and high misdiagnosis rate of OAs, it is suggested that clinical physicians update their knowledge regarding brain tumor classification and increase their awareness of rare tumor occurrence.