A misdiagnosed case of tumefactive demyelinating lesion mimicking glioma: Imaging pitfalls and diagnostic lessons.

Distinguishing cerebral glioma from tumefactive demyelinating lesion (TDL) remains a significant diagnostic challenge due to overlapping neuroimaging features despite vastly different management and prognoses. We present a case of a 51-year-old woman whose initial brain magnetic resonance imaging (MRI) was interpreted as suggestive of glioma. The patient declined surgical intervention. Follow-up MRI performed 3 months later demonstrated marked lesion reduction, supporting a demyelinating etiology. This case analyzes the factors contributing to the initial misdiagnosis, highlighting the critical role of imaging discriminators, such as the open-ring enhancement pattern, magnetic resonance spectroscopy (MRS), and perfusion-weighted imaging (PWI), as well as the value of systematic clinical reasoning in avoiding unnecessary surgical procedures.