Ganglioglioma occurring with glioblastoma multiforme: separate lesions or the same lesion?

The authors report on the first such case of ganglioglioma and a malignant variant in the same individual without prior irradiation. Gangliogliomas are frequently encountered in children and young adults and have a predilection for the temporal lobes. Sporadic cases of malignant degeneration have been reported; however, most cases have undergone radiation or subtotal resection. A 45-year-old female was seen for speech abnormalities and symptoms referable to elevated intracranial pressure. The patient had no significant past medical history and no history of neurocutaneous disorders. Two separate lesions located in the posterior and anterior temporal lobes were found on imaging. At initial surgery, she underwent gross total resection of the anterior temporal tip ganglioglioma and cyst aspiration of the posterior temporal lobe lesion. The anterior temporal lesion was a ganglioglioma and did not recur. However, the posterior temporal lesion was identified as a malignant ganglioglioma/glioblastoma multiforme variant that recurred multiple times requiring several surgeries, radiation and chemotherapy. The occurrence of these distinct entities is uncommon in patients without a history of prior radiation treatment. Even rarer, is the occurrence of these separate intracranial lesions in a patient without a history of phacomatosis. For benign gangliogliomas, gross total resection can be curative; however, more aggressive variants may be resistant to multimodal therapies.