Dysembryoplastic neuroepithelial tumors and gangliogliomas: clinical results of 52 patients

Dysembryoplastic neuroepithelial tumors (DNET) and gangliogliomas (GG) are generally associated with epilepsy in young patients. Presurgical work-up and postsurgical results vary from center to center. Seizures are commonly focal with secondary generalization, and surgical treatment is often effective. Twenty-eight patients with DNET and 24 patients with GG were eligible for this retrospective study. The authors present clinical, radiological, and pathological characteristics and seizure outcome of 52 patients histopathologically diagnosed with either a DNET or a GG. Characteristically the majority of the tumors showed hypointensity on T(1)-weighted images and increased signal intensity on both T(2)-weighted and FLAIR images. At the last follow-up (mean 54.3 months), overall favorable seizure outcome was 94.2% (n = 49). Twenty-six (92.8%) patients with DNET and 21 (87.5%) patients with GG were seizure free. Complete drug withdrawal was achieved in 26 (50%) patients. Shorter duration of epilepsy (p = 0.02), absence of status epilepticus (p = 0.01), absence of edema on MRI (p = 0.03), absence of seizure within the first month of surgery (p = 0.002), and total resection (p = 0.00001) were associated with favorable outcome with respect to seizure. Our results indicate that a prompt diagnosis and total resection with additional adjacent structures or cortices when feasible are associated with a high epilepsy cure rate. Not only children but also adults benefit from surgical treatment. Although radiological features of DNETs or GGs are helpful, no definitive differences were found between the two types of tumors. Thus, clinical, radiological, and histopathological findings have to be considered together.