With rapid development of genetic testing techniques, neuroimaging and neuroelectrophysiological technologies, our understanding of malformations of cortical development continues to be deepened and updated. In particular, mutations in genes related to the mammalian target of rapamycin (mTOR) signaling pathway have been successively discovered in focal cortical dysplasia (FCD). At the same time, the classification consensus on FCD issued by the International League Against Epilepsy (ILAE) in 2011 has encountered problems and challenges in diagnostic practice. Therefore, in 2022, ILAE proposed an updated version of the FCD classification based on the progress in molecular genetics over the past decade. The main addition to the classification system is "white matter lesions, " and it is also suggested to integrate histopathological, neuroimaging, and molecular testing results for multi-level integrated diagnosis to achieve reliable, clinically relevant, and therapeutic targeted final diagnosis.

Objective:To investigate the clinical, radiological, and pathological features of anaplastic gangliogliomas (AGGs) and to determine whether these tumors represent a distinct entity.Methods:Consecutive 667 cases of ganglioglioma (GG) diagnosed at the Xuanwu Hospital, Capital Medical University, Beijing, China between January 2015 and July 2023 were screened. Among these cases, 9 pathologically confirmed AGG cases were identified. Their clinical, radiological, treatment, and outcome data were analyzed retrospectively. Most of the tumor samples were subject to next-generation sequencing, while a subset of them were subject to DNA methylation profiling.Results:Among the 9 patients, there were five males and four females, with a median age of 8 years. Epileptic seizures (5/9) were the most frequently presented symptom. Radiological examinations showed three types of radiological manifestations: four cases showed abnormal MRI signals with no significant mass effects and mild enhancement; two cases demonstrated a mixed solid-cystic density lesion with peritumoral edema, which showed significant heterogeneous enhancement and obvious mass effects, and one case displayed cystic cavity formation with nodules on MRI, which showed evident enhancements. All cases exhibited mutations that were predicted to activate the MAP kinase signaling pathway, including seven with BRAF p.V600E mutation and two with NF1 mutation. Five AGGs with mutations involving the MAP kinase signaling pathway also had concurrent mutations, including three with CDKN2A homozygous deletion, one with a TERT promoter mutation, one with a H3F3A mutation, and one with a PTEN mutation.Conclusions:AGG exhibits a distinct spectrum of pathology, genetic mutations and clinical behaviors, differing from GG. Given these characteristics suggest that AGG may be a distinct tumor type, further expansion of the case series is needed. Therefore, a comprehensive integration of clinical, histological, and molecular analyses is required to correctly diagnose AGG. It will also help guide treatments and prognostication.

This article reports a case of adult neuronal intranuclear inclusion body disease with clinical manifestations of tremor,cognitive decline,and binocular visual impairment,which has not been clearly diagnosed and treated before.By reporting on this case,we aim to enhance physicians'understanding of adult onset of neuronuclear inclusion body disease,and to improve the diagnostic rate of neuronuclear inclusion body disease through imaging,skin biopsy,and NOTCH2NLC gene.

Malformations of cortical development (MCD) describe malformation lesions which are characterized by abnormal cortical structure or presence of heterotopic grey matter, sometimes associated with abnormal brain size. Recent progress in understanding the genetics and epigenetics in brain malformations has been driven by extraordinary advances in DNA sequencing technologies and DNA methylation profiling. For example, somatic mosaic mutations that activate mammalian target of rapamycin signaling in cortical progenitor cells are now recognized as the main cause of some types of MCD. In this review, the classification and genetic etiologies of MCD, especially focal cortical dysplasia, are summarized.

Post-transplant lymphoproliferative disorder (PTLD) is a solid organ or hematopoietic stem cells transplant associated syndrome, and central nervous system PTLD(CNS-PTLD) is extremely rare. A case of CNS-PTLD occurring after 24 years of kidney transplant was reported, and pathological examination proved it to be diffuse large B cell lymphoma. Cerebrospinal fluid next generation sequencing and pathological examination supported that Epstein-Barr virus infection was associated with it.

Objective:To analyze the clinicopathological characteristics, diagnosis and prognosis of meningioangiomatosis (MA), and to investige the possible origion of spindle cells.Methods:Seventeen cases of MA were collected at Xuanwu Hospital of Capital Medical University and the First Affiliated Hospital of Fujian Medical University, from June 2012 to March 2020. The clinical manifestations, radiologic, histopathologic, immunohistochemical features and patients′ outcome were analyzed. The presumed origin of spindle cells was evaluated by immunohistochemical staining.Results:Of the 17 patients, 9 were males and 8 were females. The age ranged from 3 to 56 years old. Thirteen patients presented with seizure as the initial symptom. The lesions were solitary and located in the cerebral cortex. Histopathologically, there were proliferation of small blood vessels and perivascular spindle cells in the cerebral cortex. The spindle cells had no obvious atypia, mitoses and necrosis. Four cases were combined with transitional meningioma. Immunohistochemically, the proliferative perivascular spindle cells were positive for vimentin in all cases, and focally positive for EMA and SSTR2. Ki-67 proliferation index was low. Neurofibrillary tangles were demonstrated by AT8. All 17 patients received surgical treatment and were followed up for one to 93 months. None had seizure attacks or tumor recurrence.Conclusions:MA is a rare slow-growing intracranial lesion, and the perivascular spindle cells could be derived from meningothelial cells, and MA is often associated with degeneration of the cerebral cortex and meningioma. The patients have good prognosis after surgical treatment.

Objective:To investigate the clinicopathological features, diagnosis and prognosis of diffuse leptomeningeal glioneuronal tumor (DLGNT).Methods:Five cases of DLGNT diagnosed from January 2016 to January 2020 were collected from Xuanwu Hospital, Capital Medical University. The clinical features, histopathologic characteristics, immunohistochemical and molecular genetic findings and prognosis were analyzed and the relevant literature was reviewed.Results:The five patients (two males and three females) were aged 2 to 52 years (median 11 years), and had history of increased intracranial pressure (headache and vomiting) or limb weakness. Three of them were younger than 16 years of age. The imaging studies showed diffuse intracranial and intraspinal nodular leptomeningeal thickening and enhancement, with or without parenchymal involvement. At times there were associated small cyst-like lesions. Imaging interpretations were inflammatory lesions in three cases and space occupying lesions in two. Microscopically, in three cases the tumors showed low to moderate cellularity, consisting of relatively monomorphous oligodendrocyte-like cells arranged in small nests or diffusely distribution. No mitosis and necrosis were observed. In two cases there were increased cellularity with a diffuse honeycomb pattern. The tumor showed mild to moderate polymorphism with hyperchromatic nuclei. Mitosis, endothelial vascular proliferation and glomeruloid vessels were seen. Necrosis was absent. The tumor cells in all five cases were positive for synaptophysin,Olig2 and negative for IDH1 and H3 K27M. GFAP was focally positive in four cases and only one case expressed NeuN partly. The Ki-67 labeling index was 1%-35%. BRAF fusion was detected in four cases. Genetic analysis showed solitary 1p deletion in two cases (2/5), while all cases were negative for 1p/19q co-deletion (0/5). The five patients were followed up for 13 to 28 months (median 15 month). One patient died after 27 months. There was no evidence of tumor progression in the remaining four patients.Conclusions:DLGNT is rare and easily confused with other central nervous system tumors and inflammatory lesions. Therefore, the diagnosis of DLGNT should be made based on comprehensive information including imaging, morphologic and corresponding immunohistochemical examinations and molecular genetics to avoid misdiagnosis and delay in management.

Belonging to the mlformations of cortical development category, focal cortical dysplasia (FCD) is a kind of desease caused by abnormal proliferation or abnormal migration of neurons in early embryo development. Epigenetics refers to changes in gene expression without changes in the nucleotide sequence of a gene, and these changes are heritable. It regulates gene expression mainly through DNA methylation, histone modification, chromatin remodeling and non-coding RNA.It is now considered that the epigenetic mechanism may be closely related to the pathogenesis of FCD, which has become a hotspot of FCD research.This paper will review the advances in epigenetic studies of FCD.