Misinterpretation of calcified oligoastrocytoma on magnetic resonance imaging

© 2013, Oncology Institute of Vojvodina, Sremska Kamenica Magnetic resonance imaging (MRI) of the brain revealed the presence of abnormal heterogeneous lesion in the left frontal lobe in a 59-year-old woman after the first grand mal seizure attack. The lesion showed the presence of central hypointense area surrounded with perifocal edema with no significant mass effect (Figure 1A). Several foci of increased T1 signal were noted within the lesion (Figure 1B). The signal abnormality was interpreted as hemorrhagic brain infarct. However, computed tomography (CT) of the brain detected the presence of calcified mass (Figure 2). Surgical removal of the tumor was performed. The histological diagnosis was grade 3 oligoastrocytoma. Since MRI is a method of choice for establishing the correct diagnosis in a great majority of neurologic disorders, especially in detection the causes of seizures, CT is becoming more frequently excluded from obligate spectrum of diagnostic protocol (1). However not only small calcifications, but even huge calcified tumors could be misinterpreted.