Objective The accurate diagnosis of the non-specific variant of dysembryoplastic neuroepithelial tumor （DNT） is very difficult because it is characterized by absence of the histological hallmark of the ＂specific gl...Objective The accurate diagnosis of the non-specific variant of dysembryoplastic neuroepithelial tumor （DNT） is very difficult because it is characterized by absence of the histological hallmark of the ＂specific glioneuronal element＂ in lesions. We herein present two cases of the non-specific form of DNT to analyze the clinical, radiological, and histological features of this unusual subtype of DNT. Methods A 16-year-old and a 23-year-old patient had been treated for pharmacoresistant epilepsy for several years before undergoing referral to the hospital for further examination and treatment. Magnetic resonance imaging （MRI） revealed that both patients had a small, well-demarcated cystic lesion within the cortex of the brain without obvious contrast enhancement or peritumoral edema. The lesions were totally resected and routinely examined using histological and immunohistochemical analysis. Results Both lesions exhibited similar histological appearances with cyst formation and mural nodule architecture. The glial nodules were mainly composed of oligodendrocyte-like components, and partly of pi^oid cells resembling pilocytic astrocytoma. The cortex adjacent to the lesion in both cases was found to have the histological features of focal cortical dysplasia （FCD） Type I. Immunohistochemically, the oligoden- drocyte-like components were diffusely positive for Syn and Olig-2, but staining for CD34, p53, and IDH1 R132H was negative. The Ki-67 （MIB-1） labeling index was low, approximately 1%. There was no 1p/19q co-deletion in either lesion by fluorescence in situ hybridization （FISH） assay. Neither patient received postoperative adjuvant treatment, and both underwent regular follow-up for at least 24 months. No signs of recurrence or epileptic attacks were observed during the follow-up period. Conclusion The non-specific variant of DNT is a diagnostic challenge for pathologists in clinical practice, and differentiation from some low-grade gliomas needs to be considered. The careful inspection of radio- logic and histopathologic findings, accompanied by analysis of patients＇ clinical manifestations, may be helpful in making an accurate diagnosis.展开更多
Background Dysembryoplastic neuroepithelial tumor （DNT） is a rare benign neoplasm of the central nervous system affecting young people. A correct preoperative diagnosis is helpful for planning surgical strategies an...Background Dysembryoplastic neuroepithelial tumor （DNT） is a rare benign neoplasm of the central nervous system affecting young people. A correct preoperative diagnosis is helpful for planning surgical strategies and improving prognosis. The purpose of this study was to characterize DNTs using magnetic resonance imaging （MRI） and magnetic resonance spectroscopy （MRS） and to analyze the value of these two techniques in the diagnosis of DNTs. Methods MR images of 13 patients with DNTs were reviewed retrospectively; and five of the patients also underwent MRS. Tumors were confirmed by surgery. The distribution, extension and signal features of the lesions were assessed, and the MRS results were analyzed. Results All tumors were supratentorial. The cortex was the main area involved, with nine tumors located in the temporal lobe, three in the frontal lobe, and one on the boundary between the temporal and occipital lobes. All cases had decreased signal intensity on Tl-weighted MR images and increased signal intensity on T2-weighted images. On fluid attenuated inversion recovery weighted images, the hyperintense ＂ring sign＂ and internal septation of the lesion were seen in 9 cases. Eight tumors had well-demarcated borders. Peritumoral edema or mass effect was absent in all cases. A contrast enhancement examination was performed in 9 cases. Contrast enhancement was absent in five cases, and four cases showed significant enhancement. The MRS showed a low N-acetylaspartate peak and a lack of elevated choline-containing component （Cho） or Cho-Cr ratio （Cho/Cr） in five patients. Conclusions The MRI findings of DNTs were stereotypical. The combination of MRI and MRS techniques were helpful in making a correct presurgical diagnosis.展开更多
Background:Dysembryoplastic neuroepithelial tumors(DNTs)are common causes of intractable epilepsy in pediatric epilepsy patients.The effect of surgical intervention is often limited when the tumor is located in the pr...Background:Dysembryoplastic neuroepithelial tumors(DNTs)are common causes of intractable epilepsy in pediatric epilepsy patients.The effect of surgical intervention is often limited when the tumor is located in the precentral gyrus.Furthermore,complete surgical resection is often not performed in order to avoid permanent neurological deficits.Methods:Here,we present a pediatric patient with intractable epilepsy caused by a simple DNT located in the precentral gyrus.Intracranial electrodes were implanted and used in combination with magnetic resonance imaging,video-electroencephalography and electrical cortical stimulation to assess neurological function,and where the epileptogenic zone was located.Results:The results of intracranial electrode monitoring suggested that the epileptogenic zone was located in the tumor area and that cortical function had been reorganized.We completely resected the tumor based on these findings.The patient has been seizure free after the surgery and has not had any neurological deficits.Conclusions:Simple form DNTs in the precentral gyrus can be completely resected with careful preoperative assessment of cortical function.Cortical reorganization could partly explain the functional preservation after surgery.展开更多
Dysembryoplastic neuroepithelial tumors （DNTs） are graded as neural and mixed neuroglial tumors （WHO Ⅰ）.They almost locate in superior tentorium lobe,and often in temporal lobe.It frequently associated with intra...Dysembryoplastic neuroepithelial tumors （DNTs） are graded as neural and mixed neuroglial tumors （WHO Ⅰ）.They almost locate in superior tentorium lobe,and often in temporal lobe.It frequently associated with intractable localization-related epilepsy in children and young adults.Its typical pathological features include disorganized arrangement of neuronal and glial elements without significant cytological atypia and frequent association of foci of dysplastic cortical disorganization.DNTs are generally regarded as essentially benign lesions,so surgical complete resection is the unique treatment without any need for chemotherapy and/or radiation therapy.Keywords：intraventricular dysembryoplastic neuroepithelial tumor; manifestation; treatment展开更多
Dysembryoplastic neuroepithelial tumors ( DNTs ), which were first describedby Daumas-Duport in 1988, are one of rare benign tumors usually associated with medicallyintractable seizures which date from childhood. The ...Dysembryoplastic neuroepithelial tumors ( DNTs ), which were first describedby Daumas-Duport in 1988, are one of rare benign tumors usually associated with medicallyintractable seizures which date from childhood. The clinical, pathologic and neuroradiologicfindings of DNT have been described. Recent advances in magnetic resonance imaging ( MRI) technologyallow the acquisition of cerebral microcirculation parameters by perfusion weighted imaging ( PWI)and brain metabolic indices by MR spectroscopy (MRS) . Several studies have shown the utility of PWIand MRS can improve the diagnostic accuracy of brain tumor, we combine the two techniques toevaluate a case with DNT and suggest that wider application of these techniques is warranted.展开更多
文摘Objective The accurate diagnosis of the non-specific variant of dysembryoplastic neuroepithelial tumor （DNT） is very difficult because it is characterized by absence of the histological hallmark of the ＂specific glioneuronal element＂ in lesions. We herein present two cases of the non-specific form of DNT to analyze the clinical, radiological, and histological features of this unusual subtype of DNT. Methods A 16-year-old and a 23-year-old patient had been treated for pharmacoresistant epilepsy for several years before undergoing referral to the hospital for further examination and treatment. Magnetic resonance imaging （MRI） revealed that both patients had a small, well-demarcated cystic lesion within the cortex of the brain without obvious contrast enhancement or peritumoral edema. The lesions were totally resected and routinely examined using histological and immunohistochemical analysis. Results Both lesions exhibited similar histological appearances with cyst formation and mural nodule architecture. The glial nodules were mainly composed of oligodendrocyte-like components, and partly of pi^oid cells resembling pilocytic astrocytoma. The cortex adjacent to the lesion in both cases was found to have the histological features of focal cortical dysplasia （FCD） Type I. Immunohistochemically, the oligoden- drocyte-like components were diffusely positive for Syn and Olig-2, but staining for CD34, p53, and IDH1 R132H was negative. The Ki-67 （MIB-1） labeling index was low, approximately 1%. There was no 1p/19q co-deletion in either lesion by fluorescence in situ hybridization （FISH） assay. Neither patient received postoperative adjuvant treatment, and both underwent regular follow-up for at least 24 months. No signs of recurrence or epileptic attacks were observed during the follow-up period. Conclusion The non-specific variant of DNT is a diagnostic challenge for pathologists in clinical practice, and differentiation from some low-grade gliomas needs to be considered. The careful inspection of radio- logic and histopathologic findings, accompanied by analysis of patients＇ clinical manifestations, may be helpful in making an accurate diagnosis.
文摘Background Dysembryoplastic neuroepithelial tumor （DNT） is a rare benign neoplasm of the central nervous system affecting young people. A correct preoperative diagnosis is helpful for planning surgical strategies and improving prognosis. The purpose of this study was to characterize DNTs using magnetic resonance imaging （MRI） and magnetic resonance spectroscopy （MRS） and to analyze the value of these two techniques in the diagnosis of DNTs. Methods MR images of 13 patients with DNTs were reviewed retrospectively; and five of the patients also underwent MRS. Tumors were confirmed by surgery. The distribution, extension and signal features of the lesions were assessed, and the MRS results were analyzed. Results All tumors were supratentorial. The cortex was the main area involved, with nine tumors located in the temporal lobe, three in the frontal lobe, and one on the boundary between the temporal and occipital lobes. All cases had decreased signal intensity on Tl-weighted MR images and increased signal intensity on T2-weighted images. On fluid attenuated inversion recovery weighted images, the hyperintense ＂ring sign＂ and internal septation of the lesion were seen in 9 cases. Eight tumors had well-demarcated borders. Peritumoral edema or mass effect was absent in all cases. A contrast enhancement examination was performed in 9 cases. Contrast enhancement was absent in five cases, and four cases showed significant enhancement. The MRS showed a low N-acetylaspartate peak and a lack of elevated choline-containing component （Cho） or Cho-Cr ratio （Cho/Cr） in five patients. Conclusions The MRI findings of DNTs were stereotypical. The combination of MRI and MRS techniques were helpful in making a correct presurgical diagnosis.
文摘Background:Dysembryoplastic neuroepithelial tumors(DNTs)are common causes of intractable epilepsy in pediatric epilepsy patients.The effect of surgical intervention is often limited when the tumor is located in the precentral gyrus.Furthermore,complete surgical resection is often not performed in order to avoid permanent neurological deficits.Methods:Here,we present a pediatric patient with intractable epilepsy caused by a simple DNT located in the precentral gyrus.Intracranial electrodes were implanted and used in combination with magnetic resonance imaging,video-electroencephalography and electrical cortical stimulation to assess neurological function,and where the epileptogenic zone was located.Results:The results of intracranial electrode monitoring suggested that the epileptogenic zone was located in the tumor area and that cortical function had been reorganized.We completely resected the tumor based on these findings.The patient has been seizure free after the surgery and has not had any neurological deficits.Conclusions:Simple form DNTs in the precentral gyrus can be completely resected with careful preoperative assessment of cortical function.Cortical reorganization could partly explain the functional preservation after surgery.
文摘Dysembryoplastic neuroepithelial tumors （DNTs） are graded as neural and mixed neuroglial tumors （WHO Ⅰ）.They almost locate in superior tentorium lobe,and often in temporal lobe.It frequently associated with intractable localization-related epilepsy in children and young adults.Its typical pathological features include disorganized arrangement of neuronal and glial elements without significant cytological atypia and frequent association of foci of dysplastic cortical disorganization.DNTs are generally regarded as essentially benign lesions,so surgical complete resection is the unique treatment without any need for chemotherapy and/or radiation therapy.Keywords：intraventricular dysembryoplastic neuroepithelial tumor; manifestation; treatment
文摘Dysembryoplastic neuroepithelial tumors ( DNTs ), which were first describedby Daumas-Duport in 1988, are one of rare benign tumors usually associated with medicallyintractable seizures which date from childhood. The clinical, pathologic and neuroradiologicfindings of DNT have been described. Recent advances in magnetic resonance imaging ( MRI) technologyallow the acquisition of cerebral microcirculation parameters by perfusion weighted imaging ( PWI)and brain metabolic indices by MR spectroscopy (MRS) . Several studies have shown the utility of PWIand MRS can improve the diagnostic accuracy of brain tumor, we combine the two techniques toevaluate a case with DNT and suggest that wider application of these techniques is warranted.
