Dysembryoplastic neuroepithelial tumor: A rare brain tumor not to be misdiagnosed

Imaging of pediatric glioneuronal and neuronal tumors

Glioneuronal tumors (GNTs) are an expanding group of primary CNS neoplasms, commonly affecting children, adolescents and young adults. Most GNTs are relatively indolent, low-grade, WHO grade I lesions. In the pediatric age group, GNTs have their epicenter in the cerebral cortex and present with seizures. Alterations in the mitogen-activated protein kinase (MAPK) pathway, which regulates cell growth, are implicated in tumorigenesis. Imaging not only plays a key role in the characterization and pre-surgical evaluation of GNTs but is also crucial role in follow-up, especially with the increasing use of targeted inhibitors and immunotherapies. In this chapter, we review the clinical and imaging perspectives of common pediatric GNTs.

The importance of neuroimaging methods in the diagnosis of epilepsy in young men: literature review and own clinical case

Lifetime visualization of structural morphological changes of the brain in patients suffering from epilepsy and epileptic syndromes has become possible due to the introduction of neuroimaging methods into everyday medical practice. At the same time, neuroimaging is the main method of determining the etiology of epilepsy and its taxonomic position. One of these methods is magnetic resonance imaging (MRI). MRI is the method of choice in the examination of patients with diseases associated with brain development abnormalities. The aim of this study is to consider the importance of using neuroimaging methods in this clinical case of epilepsy in a young person, taking into account complaints, anamnesis of the disease and life, neurological status, laboratory results for the correct diagnosis. Conclusion. The presented clinical case of symptomatic epilepsy with focal vegetative-sensory seizures of medium frequency due to mass formation of the medial part of the right temporal lobe demonstrates the need and importance of a comprehensive examination using neuroimaging methods to clarify the etiology of the disease. Thus, magnetic resonance imaging has a high diagnostic value. This article discusses the importance of MRI for the diagnosis of epilepsy and its etiology in a young man.

Dysembryoplastic Neuroepithelial Tumor: A Rare Brain Tumor with Excellent Seizure Control after Surgical Resection

Introduction Dysembryoplastic neuroepithelial tumor (DNET) is a rare cause of intractable epilepsy, which has excellent results in terms of seizure control after surgical resection. We present one such case, because of its rarity, to highlight the effect of tumor removal on seizure control, particularly DNET.

Materials and Methods/Case Summary A 9-year-old male patient presented with sudden onset of partial seizures for the past 6 months. There were five episodes. In each episode, the patient engaged in irrelevant talk, followed by deviation of mouth to left and twitching movements. The episode lasted 5 minutes and there was no loss of consciousness. There was no aura or tongue bite, and in one of the episodes, the patient lost consciousness. There was no other significant positive history. On examination, the child was consciously alert, without focal neurological deficit or features of meningitis. There was no papilledema. The patient was on phenytoin sodium, phenobarbitone and clobazam. Magnetic resonance imaging (MRI) of brain was done with and without contrast. MRI revealed a lesion approximately 4.1 × 3.6 × 3.2 cm in the right medial temporal lobe. It was hypointense to brain on T1 and fluid-attenuated inversion recovery (FLAIR), and hyperintense on T2-weighted images. Diffusion restriction was present and there was minimal contrast uptake. There was no evidence of mass effect or midline shift After discussing the risks and benefits with parents, the patient underwent preanesthetic checkup, and was taken up for craniotomy and excision of tumor. Gross total excision was done. The child was started orally on day 1 postoperatively and ambulated. There were no further seizure episodes. The patient was continued on phenytoin and clobazam, and phenobarbitone was tapered gradually. At 6 months, the child was seizure-free.

Conclusions DNET are rare tumors occurring early in life and presenting with intractable seizures. Surgical resection offers a good and safe chance for long-term seizure control.

Pediatric Low-Grade Gliomas

Brain tumors constitute the largest source of oncologic mortality in children and low-grade gliomas are among most common pediatric central nervous system tumors. Pediatric low-grade gliomas differ from their counterparts in the adult population in their histopathology, genetics, and standard of care. Over the past decade, an increasingly detailed understanding of the molecular and genetic characteristics of pediatric brain tumors led to tailored therapy directed by integrated phenotypic and genotypic parameters and the availability of an increasing array of molecular-directed therapies. Advances in neuroimaging, conformal radiation therapy, and conventional chemotherapy further improved treatment outcomes. This article reviews the current classification of pediatric low-grade gliomas, their histopathologic and radiographic features, state-of-the-art surgical and adjuvant therapies, and emerging therapies currently under study in clinical trials.

Dysembryoplastic Neuroepithelial Tumors: What You Need to Know

OBJECTIVE

An updated and comprehensive review on dysembryoplastic neuroepithelial tumor (DNET) focusing on differential diagnosis, atypical presentation, seizure outcome, and risk of malignant transformation.

METHODS

A PubMed/MEDLINE-based literature search has been performed using "dysembryoplastic neuroepithelial tumor" as a keyword. Two treated cases characterized by an atypical presentation have been reviewed.

RESULTS

Of 1162 articles, 200 relevant studies have been selected. DNET is a benign mixed neuronal-glial tumor causing drug-resistant epilepsy primarily in children and young adults. The typical radiological pattern is a magnetic resonance imaging (MRI) T1-hypointense, T2-, and fluid-attenuated inversion-recovery hyperintense multicystic lesion involving the cerebral cortex with no edema. Contrast enhancement may be present and a focal cortical dysplasia is commonly associated with it. MRI diffusion, perfusion, and spectroscopy have a paramount role in the differential diagnosis. The "specific glioneuronal elements" are pathognomonic. They are positive for S100 protein, synaptofisin, neuronal nuclei, oligodendrocyte transcription factor, neurite outgrowth inhibitor, and microtubule-associated protein 2, but negative for glial fibrillary acidic protein. As opposed to v-myb avian myeloblastosis viral oncogene homolog, isocitrate dehydrogenase-1/isocitrate dehydrogenase-2 mutation and codeletion 1p-19q, fibroblast growth factor receptor 1 and BRAF V600E mutations are present. The effectiveness of surgery on seizure outcome has been established. Rare malignant transformations have been reported, especially in extra-temporal and complex forms.

CONCLUSIONS

Advanced MRI techniques are fundamental in the differential diagnosis for DNET versus other low-grade gliomas. Immuno-phenotype assessment and search for fibroblast growth factor receptor 1 and BRAF V600E mutations limit the risk of misdiagnoses. A gross total tumor removal is generally associated with a seizure-free outcome. Recurrences and malignant transformations may rarely follow, legitimizing MRI surveillance in cases of subtotal tumor resection.