Dysembryoplastic neuroepithelial tumors. Analysis of 16 cases.

Objectives. - We report on 16 cases of dysembryoplastic Neuroepithelial tumor (DNT) treated in the Nancy University Hospital from 1987 to 1997 Patients and methods. - There were 9 males and 7 females. Mean age at onset of symptoms was 9.5 years (range: 3 months to 29 years) and the mean age at surgery was 16 years. Nine patients experienced partial complex seizures, 5 patients generalized seizures, I patient partial seizures with secondary generalization and one patient ataxia. The diagnosis of DNT was made under consideration of clinical, radiological and neuropathological features. All patients underwent surgery. Results. - Removal of the tumor was complete for 10 patients, subtotal or partial for 6 patients. Histological examination revealed that 7 cases were specific forms of DNT due to the presence of the specific glioneuronal element. For the 9 remained cases, the diagnosis of DNT could only be mane with the consideration of clinical and radiological features. Mean post-surgical follow-rip was 3.5 years (range : 1-8 years). Fight patients were seizures-free, 7 had a significative reduction in seizures frequency with minimal anti-convulsivant treatment. The patient with ataxia remained unchanged. Far the patients with partial resection of the tumor, follow-up MRI and CT scan showed no significant growth of the remnant and the remaining patients have had no recurrence to date. Conclusion. - The recognition of this surgically curable entity is mandatory. Knowledge of the good prognosis associated with the DNT is essential to avoid deleterious side effects of overtreatment by radiotherapy and/or chemotherapy.