Early presentation of de novo high grade glioma with epileptic seizures: electroclinical and neuroimaging findings.

We report the clinical, EEG and neuroradiologic findings from three adult patients who developed new-onset seizure disorders as early clinical manifestations of de novo high grade glioma. The malignancies could not be recognised at the time of the first epileptic seizure because of minimal non-specific brain abnormalities, which showed no signs of necrosis or significant contrast enhancement on computed tomography and magnetic resonance imaging. Focal EEG abnormalities were recorded in all cases and appeared consistent with the neuroradiologic findings. The patients regained normal neurological status after the first seizure but rapidly developed space-occupying necrotic lesions. Two patients underwent surgery and received histological diagnoses of the tumours. Another patient was finally diagnosed with a malignant glioma based on the neuroradiologic picture and rapid progression of the cerebral lesion. It should be noted that in adult patients, new-onset epileptic seizures might reveal the presence of malignant gliomas at a very early stage in the tumour formation process. This report indicates that typical anatomoradiologic features of de novo high grade glioma, such as necrosis and rim-contrast enhancement, could be absent at the time of the first epileptic seizure but become clear within a short period after clinical presentation.