CLINICAL ARTICLE Dysembryoplastic neuroepithelial tumors and gangliogliomas: clinical results of 52 patients Fatma Ozlen & Aysegul Gunduz & Ziya Asan & Taner Tanriverdi & Cigdem Ozkara & Naz Yeni & Cengiz Yalcinkaya & Emin Ozyurt & Mustafa Uzan Received: 30 March 2010 / Accepted: 18 May 2010 / Published online: 5 June 2010 # Springer-Verlag 2010 Abstract Purpose 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. Methods 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 histo- pathologically diagnosed with either a DNET or a GG. Results 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. Conclusions 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. Keywords Dysembryoplastic neuroepithelial tumor . Epilepsy . Ganglioglioma . Glioneuronal tumor . Seizure outcome Introduction Epilepsy is a common cause of morbidity in approximately one third of patients with primary brain tumors and seizure control by medical treatment seems to be less effective because of incomplete understanding of underlying patho- physiological mechanism(s) [1]. Epilepsy secondary to primary brain tumors are generally focal and could be the first manifestation. Location, type, and growth patterns of brain tumors are common factors that afflict a patient who likely exhibits a seizure activity. Clinical studies have clearly demonstrated that slow-growing tumors, as the name implies, grow slowly and invade surrounding structures and have the highest frequency of seizure compared to fast-growing tumors [2]. Particularly the growth pattern of an intracranial tumor has both structural and functional consequences on the surrounding structures in which edema, inflammation, and metabolic changes take place [2]. The better understanding of such consequences in F. Ozlen : Z. Asan : T. Tanriverdi : E. Ozyurt : M. Uzan (*) Department of Neurosurgery, Cerrahpasa Medical Faculty, Istanbul University, Istanbul, Turkey e-mail: uzan@istanbul.edu.tr A. Gunduz : C. Ozkara : N. Yeni : C. Yalcinkaya Department of Neurology, Cerrahpasa Medical Faculty, Istanbul University, Istanbul, Turkey Acta Neurochir (2010) 152:1661–1671 DOI 10.1007/s00701-010-0696-4