gms | German Medical Science

Objective: Dysembryoplastic Neuroepithelial Tumor (DNET) is a rare, usually benign pediatric brain tumor that is presenting generally with seizures. The optimal management and long-term outcome is uncertain. The goal of this study was to evaluate the role of surgery for seizure control.

Method: We retrospectively reviewed all patients identified with a DNET who presented during 1997 to 2015. Patient demographics, clinical presentation, operative procedures, pathology, and outcome were determined.

Results: Of the 28 patients (17male, 11 female) identified, 26 (95%) presented with seizures at an average age of 7.3 yrs. The most common seizure presentation was partial complex, or with secondary generalization (15 versus 11 cases). The most common tumor location was frontal or temporal (15 versus 11 cases). Average duration of follow-up was 5.5 yrs. 14 of 17 patients who underwent a gross total excision were seizure free off medication compared to 4 of 9 patients with residual tumor. One patient with early tumor regrowth received radiation therapy. He subsequently received chemotherapy as he was showing evidence of dissemination. Repeat resection 4 years after initial diagnosis revealed malignant transformation with BAF47 negative cells, suggestive of atypical rhabdoid teratoid tumor. All patients are alive at last follow-up.

Conclusions: Pediatric DNET tumors are rare tumors with an excellent overall prognosis. Gross total excision provides tumor and seizure control. Tumors not amenable to complete excision are more problematic and require ongoing surveillance. The need for adjuvant treatment is exceptional and should raise the issue of some atypical DNET that may have a different behavior.