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Aims: To investigate the value of previously described pretreatment hematological and biochemical biomarkers as predictors of pathological response. Methods: The authors performed a retrospective analysis of 191 patients with locally advanced rectal cancer who underwent long-course neoadjuvant chemoradiotherapy at two Portuguese centers. The authors performed logistic regression analysis to search for predictive markers of pathological complete and good response. Results: High platelet–neutrophil index (p = 0.042) and clinical tumor stage >2 (p = 0.015) were predictive of poor response. None of the analyzed biomarkers predicted pathological complete response in this study. Conclusion: A high platelet–neutrophil index before neoadjuvant chemoradiotherapy could help predict poorer pathological response in patients with locally advanced rectal cancer. However, no other blood biomarker predicted incomplete or poor response in this study.

OSNA is a molecular assay for the detection of sentinel node metastasis. TTL emerged as a concept that seems to accurately predict the status of the NSN. Authors tried to confirm this motion. This is a retrospective and multicentric study that analyzed 2164 patients, 579 of whom had positive SN and completion AD. Logistic regression models were performed in order to identify a suitable cutoff to identify patients who benefit from AD. Univariate and multivariate regression analysis showed a relationship between TTL>30000 and the presence of NSN metastasis (OR 2.84, CI 1.99–4.08, p < 0.001). Logistic regression indicated that the cutoff of 30000 copies/μL better discriminates patients with NSN positivity and allows wide use of these criteria. This cutoff value may safely assist clinicians and patients to decide to proceed or not with an AD. There was no sponsorship.

High-grade gliomas (HGG) remain one of the most aggressive tumors, which is primarily due to its diffuse infiltrative nature. Serine proteases and metalloproteases are known to play key roles in cellular migration and invasion mechanisms. SPINT2, also known as HAI-2, is an important serine protease inhibitor that can affect MET signaling. SPINT2 has been found to be frequently downregulated in various tumors, whereby hypermethylation of its promoter appears to serve as a common mechanism. Here, we assessed the clinical relevance of SPINT2 expression and promoter hypermethylation in pediatric and adult HGG and explored its functional role. A series of 371 adult and 77 pediatric primary HGG samples was assessed for SPINT2 protein expression (immunohistochemistry) and promoter methylation (methylation-specific PCR) patterns. After SPINT2 knockdown and knock-in in adult and pediatric HGG cell lines, a variety of in vitro assays was carried out to determine the role of SPINT2 in glioma cell viability and invasion, as well as their mechanistic associations with metalloprotease activities. We found that SPINT2 protein expression was frequently absent in adult (85.3%) and pediatric (100%) HGG samples. The SPINT2 gene promoter was found to be hypermethylated in approximately half of both adult and pediatric gliomas. Through functional assays we revealed a suppressor activity of SPINT2 in glioma cell proliferation and viability, as well as in their migration and invasion. These functions appear to be mediated in part by MMP2 expression and activity. We conclude that dysregulation of SPINT2 is a common event in both pediatric and adult HGG, in which SPINT2 may act as a tumor suppressor.

Background The minor salivary glands’ biopsy is a minimally invasive procedure used for the diagnosis of Sjogren's syndrome. Its significance has also been reported in other inflammatory/infiltrative diseases. The objectives are to investigate its use in the diagnosis of Sjogren's syndrome, as well as to evaluate its role in the diagnosis of amyloidosis and sarcoidosis. Methods A retrospective analysis was carried out on patients who underwent minor salivary glands’ biopsies between April of 2014 and December of 2017. Results A total of 173 patients were identified. Of the patients with suspected Sjogren's syndrome, in 40% of the cases there was evidence of lymphocytic sialadenitis. The antibodies against SSA, antinuclear antibodies and the Rheumatoid Factor correlated significantly with the presence of lymphocytic sialadenitis. The result of the minor salivary glands’ biopsies allowed an increase of 12.4% of patients who met the criteria defined by the American – European Consensus Group. Of the patients with suspected amyloidosis (25%), the biopsies were positive in 4 patients. Conclusion The minor salivary glands’ biopsy is a simple procedure with effectiveness in the diagnosis of Sjogren's syndrome and amyloidosis. In this study, its use increased the number of patients who met the Sjogren's syndrome classification criteria. It also appears to be useful in the diagnosis of amyloidosis.

Background Surgery is a widely accepted treatment option for drug-resistant focal epilepsy. A detailed analysis of longitudinal postoperative seizure outcomes and use of antiepileptic drugs for different brain lesions causing epilepsy is not available. We aimed to analyse the association between histopathology and seizure outcome and drug freedom up to 5 years after epilepsy surgery, to improve presurgical decision making and counselling.Methods In this retrospective, multicentre, longitudinal, cohort study, patients who had epilepsy surgery between Jan 1, 2000, and Dec 31, 2012, at 37 collaborating tertiary referral centres across 18 European countries of the European Epilepsy Brain Bank consortium were assessed. We included patients of all ages with histopathology available after epilepsy surgery. Histopathological diagnoses and a minimal dataset of clinical variables were collected from existing local databases and patient records. The primary outcomes were freedom from disabling seizures (Engel class 1) and drug freedom at 1, 2, and 5 years after surgery. Proportions of individuals who were Engel class 1 and drug-free were reported for the 11 main categories of histopathological diagnosis. We analysed the association between histopathology, duration of epilepsy, and age at surgery, and the primary outcomes using random effects multivariable logistic regression to control for confounding.Findings 9147 patients were included, of whom seizure outcomes were available for 8191 (89.5%) participants at 2 years, and for 5577 (61.0%) at 5 years. The diagnoses of low-grade epilepsy associated neuroepithelial tumour (LEAT), vascular malformation, and hippocampal sclerosis had the best seizure outcome at 2 years after surgery, with 77.5% (1027 of 1325) of patients free from disabling seizures for LEAT, 74.0% (328 of 443) for vascular malformation, and 71.5% (2108 of 2948) for hippocampal sderosis. The worst seizure outcomes at 2 years were seen for patients with focal cortical dysplasia type I or mild malformation of cortical development (50.0%, 213 of 426 free from disabling seizures), those with malformation of cortical development-other (52.3%, 212 of 405 free from disabling seizures), and for those with no histopathological lesion (53.5%, 396 of 740 free from disabling seizures). The proportion of patients being both Engel class 1 and drug-free was 0-14% at 1 year and increased to 14-51% at 5 years. Children were more often drug-free; temporal lobe surgeries had the best seizure outcomes; and a longer duration of epilepsy was associated with reduced chance of favourable seizure outcomes and drug freedom. This effect of duration was evident for all lesions, except for hippocampal sclerosis.Interpretation Histopathological diagnosis, age at surgery, and duration of epilepsy are important prognostic factors for outcomes of epilepsy surgery. In every patient with refractory focal epilepsy presumed to be lesional, evaluation for surgery should be considered. Copyright (C) 2020 Elsevier Ltd. All rights reserved.

Objective The microscopic review of hematoxylin-eosin-stained images of focal cortical dysplasia type IIb and cortical tuber of tuberous sclerosis complex remains challenging. Both entities are distinct subtypes of human malformations of cortical development that share histopathological features consisting of neuronal dyslamination with dysmorphic neurons and balloon cells. We trained a convolutional neural network (CNN) to classify both entities and visualize the results. Additionally, we propose a new Web-based deep learning application as proof of concept of how deep learning could enter the pathologic routine. Methods A digital processing pipeline was developed for a series of 56 cases of focal cortical dysplasia type IIb and cortical tuber of tuberous sclerosis complex to obtain 4000 regions of interest and 200 000 subsamples with different zoom and rotation angles to train a neural network. Guided gradient-weighted class activation maps (Guided Grad-CAMs) were generated to visualize morphological features used by the CNN to distinguish both entities. Results Our best-performing network achieved 91% accuracy and 0.88 area under the receiver operating characteristic curve at the tile level for an unseen test set. Novel histopathologic patterns were found through the visualized Guided Grad-CAMs. These patterns were assembled into a classification score to augment decision-making in routine histopathology workup. This score was successfully validated by 11 expert neuropathologists and 12 nonexperts, boosting nonexperts to expert level performance. Significance Our newly developed Web application combines the visualization of whole slide images with the possibility of deep learning-aided classification between focal cortical dysplasia IIb and tuberous sclerosis complex. This approach will help to introduce deep learning applications and visualization for the histopathologic diagnosis of rare and difficult-to-classify brain lesions.

We trained a convolutional neural network (CNN) to classify H.E. stained microscopic images of focal cortical dysplasia type IIb (FCD IIb) and cortical tuber of tuberous sclerosis complex (TSC). Both entities are distinct subtypes of human malformations of cortical development that share histopathological features consisting of neuronal dyslamination with dysmorphic neurons and balloon cells. The microscopic review of routine stainings of such surgical specimens remains challenging. A digital processing pipeline was developed for a series of 56 FCD IIb and TSC cases to obtain 4000 regions of interest and 200.000 sub-samples with different zoom and rotation angles to train a CNN. Our best performing network achieved 91% accuracy and 0.88 AUCROC (area under the receiver operating characteristic curve) on a hold-out test-set. Guided gradient-weighted class activation maps visualized morphological features used by the CNN to distinguish both entities. We then developed a web application, which combined the visualization of whole slide images (WSI) with the possibility for classification between FCD IIb and TSC on demand by our pretrained and build-in CNN classifier. This approach might help to introduce deep learning applications for the histopathologic diagnosis of rare and difficult-to-classify brain lesions.

Human hotspot TERT promoter (TERTp) mutations have been reported in a wide range of tumours. Several studies have shown that TERTp mutations are associated with clinicopathological features; in some instances, TERTp mutations were considered as biomarkers of poor prognosis. The rs2853669 SNP, located in the TERT promoter region, was reported to modulate the increased TERT expression levels induced by the recurrent somatic mutations. In this study we aimed to determine the frequency and prognostic value of TERTp mutations and TERT rs2853669 SNP in 504 gliomas from Portuguese and Brazilian patients. TERTp mutations were detected in 47.8% of gliomas (216/452). Glioblastomas (GBM) exhibited the highest frequency of TERTp mutations (66.9%); in this glioma subtype, we found a significant association between TERTp mutations and poor prognosis, regardless of the population. Moreover, in a multivariate analysis, TERTp mutations were the only independent prognostic factor. Our data also showed that the poor prognosis conferred by TERTp mutations was restricted to GBM patients carrying the rs2853669 A allele and not in those carrying the G allele. In conclusion, the presence of TERTp mutations was associated with worse prognosis in GBM patients, although such association depended on the status of the rs2853669 SNP. The status of the rs2853669 SNP should be taken in consideration when assessing the prognostic value of TERTp mutations in GBM patients. TERTp mutations and the rs2853669 SNP can be used in the future as biomarkers of glioma prognosis.

© Springer-Verlag GmbH Germany, part of Springer Nature 2019., The "isomorphic subtype of diffuse astrocytoma" was identified histologically in 2004 as a supratentorial, highly differentiated glioma with low cellularity, low proliferation and focal diffuse brain infiltration. Patients typically had seizures since childhood and all were operated on as adults. To define the position of these lesions among brain tumours, we histologically, molecularly and clinically analysed 26 histologically prototypical isomorphic diffuse gliomas. Immunohistochemically, they were GFAP-positive, MAP2-, OLIG2- and CD34-negative, nuclear ATRX-expression was retained and proliferation was low. All 24 cases sequenced were IDH-wildtype. In cluster analyses of DNA methylation data, isomorphic diffuse gliomas formed a group clearly distinct from other glial/glio-neuronal brain tumours and normal hemispheric tissue, most closely related to paediatric MYB/MYBL1-altered diffuse astrocytomas and angiocentric gliomas. Half of the isomorphic diffuse gliomas had copy number alterations of MYBL1 or MYB (13/25, 52%). Gene fusions of MYBL1 or MYB with various gene partners were identified in 11/22 (50%) and were associated with an increased RNA-expression of the respective MYB-family gene. Integrating copy number alterations and available RNA sequencing data, 20/26 (77%) of isomorphic diffuse gliomas demonstrated MYBL1 (54%) or MYB (23%) alterations. Clinically, 89% of patients were seizure-free after surgery and all had a good outcome. In summary, we here define a distinct benign tumour class belonging to the family of MYB/MYBL1-altered gliomas. Isomorphic diffuse glioma occurs both in children and adults, has a concise morphology, frequent MYBL1 and MYB alterations and a specific DNA methylation profile. As an exclusively histological diagnosis may be very challenging and as paediatric MYB/MYBL1-altered diffuse astrocytomas may have the same gene fusions, we consider DNA methylation profiling very helpful for their identification., This study was supported by an International League against Epilepsy (ILAE) Grant to D. Capper. I. Blumcke was supported by the European Union (FP6 DESIRE Grant Agreement #602531). M. Mittelbronn would like to thank the Luxembourg National Research Fund (FNR) for the support (FNR PEARL P16/BM/11192868 grant). K. Ligon is funded by the Paediatric Low Grade Astrocytoma Foundation and NCI R01CA215489. T. Jacques is funded by The Brain Tumour Charity, Children with Cancer UK, Great Ormond Street Hospital Children’s Charity, Cancer Research UK, the Olivia Hodson Cancer Fund and the National Institute of Health Research. T. Jacques’s work is partly funded by the NIHR GOSH BRC. The views expressed are those of the authors and not necessarily those of the NHS, the NIHR or the Department of Health. We thank the biomedical scientists in the Division of Neuropathology, the National Hospital for Neurology and Neurosurgery (NHNN) for excellent technical assistance. We also thank clinicians and neuropathologists for referring cases for molecular analysis. Part of the study was funded by the National Institute for Health Research to UCLH Biomedical research centre (BRC399/NS/RB/101410). S. Brandner and Z. Jaunmuktane are also supported by the Department of Health’s NIHR Biomedical Research Centre’s funding scheme. Additional funding was provided by the Brain Tumour Charity (UK) for the Everest Centre for Paediatric Low-Grade Brain Tumour Research

Low-grade epilepsy-associated brain tumours (LEAT) are the second most common cause for drug-resistant, focal epilepsy, that is ganglioglioma (GG) and dysembryoplastic neuroepithelial tumours (DNT). However, molecular pathogenesis, risk factors for malignant progression and their frequent association with drug-resistant focal seizures remain poorly understood. This contrasts recent progress in understanding the molecular-genetic basis and targeted treatment options in diffuse gliomas. The Neuropathology Task Force of the International League Against Epilepsy examined available literature to identify common obstacles in diagnosis and research of LEAT. Analysis of 10 published tumour series from epilepsy surgery pointed to poor inter-rater agreement for the histopathology diagnosis. The Task Force tested this hypothesis using a web-based microscopy agreement study. In a series of 30 LEAT, 25 raters from 18 countries agreed in only 40% of cases. Highest discordance in microscopic diagnosis occurred between GG and DNT variants, when oligodendroglial-like cell patterns prevail, or ganglion cells were difficult to discriminate from pre-existing neurons. Suggesting new terminology or major histopathological criteria did not satisfactorily increase the yield of histopathology agreement in four consecutive trials. To this end, the Task Force applied the WHO 2016 strategy of integrating phenotype analysis with molecular-genetic data obtained from panel sequencing and 450k methylation arrays. This strategy was helpful to distinguish DNT from GG variants in all cases. The Task Force recommends, therefore, to further develop diagnostic panels for the integration of phenotype-genotype analysis in order to reliably classify the spectrum of LEAT, carefully characterize clinically meaningful entities and make better use of published literature.

Aim Polymicrogyria (PMG) is one of the most common forms of cortical malformation yet the mechanism of its development remains unknown. This study describes the histopathological aspects of PMG in a large series including a significant proportion of fetal cases. Method We have reviewed the neuropathology and medical records of 44 fetuses and 27 children and adults in whom the cortical architecture was focally or diffusely replaced by one or more festooning bands of neurons. Results The pial surface of the brain overlying the polymicrogyric cortex was abnormal in almost 90% of cases irrespective of the aetiology. This accords with animal studies indicating the importance of the leptomeninges in cortical development. The aetiology of PMG was highly heterogeneous and there was no correlation between cortical layering patterns and aetiology. PMG was almost always associated with other brain malformations. Interpretation The inclusion of many fetal cases has allowed us to examine the early developmental stages of PMG. The study indicates the significance of surface signals responsible for human corticogenesis and the complex interaction between genetic and environmental factors leading to this common endpoint of cortical maldevelopment.

ObjectiveTo investigate if intracranial EEG patterns at seizure onset can predict surgical outcome.MethodsIctal onset patterns from intracranial EEG were analysed in 373 electro-clinical seizures and subclinical seizures from 69 patients. Seizure onset patterns were classified as: (a) Diffuse electrodecremental (DEE); (b) Focal fast activity (FA); (c) Simultaneous onset of fast activity and diffuse electrodecremental event (FA-DEE); (d) Spikes; (e) Spike-wave activity; (f) Sharp waves; (g) Alpha activity; (h) Delta activity. Presence of preceding epileptiform discharge (PED) was also studied. Engel and ILAE surgical outcome scales were used.ResultsThe mean follow-up period was 42.1 months (SD = 30.1). Fast activity was the most common seizure onset pattern seen (33%), followed by (FA-DEE) (20%), DEE (19%), spike-wave activity (12%), sharp-waves (6%), alpha activity (6%), delta activity (3%) and spikes (1%). Preceding epileptiform discharges were present in 75% of patients. FA was associated with favourable outcome (p = 0.0083) whereas DEE was associated with poor outcome (p = 0.0025). A widespread PED was not associated with poor outcome (p = 0.9559). There was no clear association between seizure onset pattern and specific pathology, except possibly between sharp/spike waves and mesial temporal sclerosis.ConclusionsFA activity is associated with favourable outcome. DEE at onset was associated with poor surgical outcome. Widespread/bilateral PEDs were not associated with poor or good outcome.SignificanceFA appears to be the best marker for the epileptogenic zone. Surgery should be contemplated with caution if DEE is the first ictal change. However, a widespread/bilateral PED at onset is common and should not discourage surgery.

We describe the case of a 69-year-old man who presented with symptoms of headache and severe vision loss due to G4 immunoglobulin (IgG4) hypertrophic pachymeningitis (HP). The patient was initially responsive to corticotherapy, but vision loss progressed when steroid therapy was first tapered. No improvement was noticed with intravenous rituximab. The patient showed clinical and radiological improvement after intrathecal rituximab, which can be an efficacious alternative treatment option.

Background Basal cell carcinoma (BCC) is the most frequent skin cancer. An elevated prevalence of BCC has been associated with radiation, namely after the Tinea capitis epilation treatment, being these tumors described as more aggressive. Mitochondrial DNA (mtDNA) mutations have been reported in many human tumors, but their occurrence in BCC is poorly documented. Objective The purpose of this work was to evaluate BCC histological subtypes in individuals subjected to X-ray epilation for Tinea capitis treatment when compared to non-irradiated patients. Moreover we also wanted to evaluate mitochondrial D-Loop instability in both groups of BCCs in order to compare the frequency of D-Loop mutations in post-irradiation BCC versus sporadic BCC. Methods 228 histological specimens corresponding to BCCs from 75 irradiated patients and 60 non-irradiated patients were re-evaluated for histological subtype. Subsequently, we sequenced the D-Loop 310 repeat in blood, oral mucosa, tumor lesions and, whenever available, non-tumoral adjacent tissue from these patients. Results The infiltrative subtype of BCC, considered to be more aggressive, was significantly more frequent in irradiated patients. BCC D-Loop D310 mutation rate was significantly higher in irradiated BCCs than in the non-irradiated ones. Moreover, it was associated with a higher irradiation dose. The presence of mtDNA heteroplasmy in patients’ blood was associated with a higher mutation rate in the BCCs suggesting that a more unstable genotype could predispose to mtDNA somatic mutation. Conclusions Our results suggest that radiation-induced BCCs may be considered to be more aggressive tumors. Further studies are needed to clarify the role of mtDNA D-Loop mutations in tumors from irradiated patients.

Purpose Predicting seizure control after epilepsy surgery is difficult. The objectives of this work are: (a) to estimate the value of surgical procedure, presence of neuroimaging abnormalities, need for intracranial recordings, resection lobe, pathology, durations of epilepsy and follow-up period to predict postsurgical seizure control after epilepsy surgery and (b) to provide empirical estimates of successful outcome after different combinations of the above factors in order to aid clinicians in advising patients presurgically about the likelihood of success under their patients' individual circumstances. Methods We report postsurgical seizure control from all 243 patients who underwent resective surgery for epilepsy at King's College Hospital between 1999 and 2011. Among the 243 patients, 233 had lobar or sub-lobar resections, 8 had multilobar resections and 2 had excision of a hypothalamic hamartoma. We examined the relation between postsurgical seizure control and type of surgical procedure, presence of neuroimaging abnormalities, pathology, resection lobe and the need of intra-cranial electrodes to identify seizure onset. Results Among the 243 patients, 126 (52%) enjoyed outcome grade I, 40 (16%) had grade II, 51 (21%) had grade III and 26 (11%) had grade IV (mean follow-up 41.1 months). Normal neuroimaging or need for intracranial recordings was not associated with poorer outcome. Patients undergoing temporal resections showed better outcome than those with frontal resections, due to the poor outcome seen in frontal patients with normal neuroimaging. Among temporal resections, there was no difference in outcome between patients with and without neuroimaging abnormalities. Among patients with lesions on imaging, temporal and frontal resections showed similar outcomes. Likelihood of favourable outcome under the patient's individual circumstances was estimated by the tables provided. There was an 8–9% decrease in the percentage of grade I between follow-up at 12 and >36 months. Conclusion Overall, nearly 70% of patients undergoing resective surgery enjoy favourable post-surgical seizure control. Normal neuroimaging should not discourage surgery in temporal patients but is a negative prognostic sign in normal MRI frontal patients. There were no statistical differences in outcome between patients with neuroimaging lesions in frontal or temporal lobes.

Rapid developments in molecular genetic technology and research have swiftly advanced our understanding of neuro-oncology. As a consequence, the WHO invited their expert panels to revise the current classification system of brain tumours and to introduce, for the first time, a molecular genetic approach for selected tumour entities, thus setting a new gold standard in histopathology. The revised 5th edition of the 'blue book' was released in May 2016 and will have a major impact in stratifying diagnosis and treatment. However, low-grade neuroepithelial tumours that present with early-onset focal epilepsy and are mostly seen in children and young adults (previously designated as long-term epilepsy-associated neuroepithelial tumours, LEAT) lack such innovative clinicopathological and molecular genetic tools. The Neuropathology Task Force of the International League against Epilepsy will critically discuss this issue, and will offer perspectives on how to decipher and validate clinically meaningful LEAT entities using the current WHO approach that integrates clinicopathological and genetic classification systems.

Background: Glioblastomas (GBM) present a high cellular heterogeneity with conspicuous necrotic regions associated with hypoxia, which is related to tumor aggressiveness. GBM tumors exhibit high glycolytic metabolism with increased lactate production that is extruded to the tumor microenvironment through monocarboxylate transporters (MCTs). While hypoxia-mediated regulation of MCT4 has been characterized, the role of MCT1 is still controversial. Thus, we aimed to understand the role of hypoxia in the regulation of MCT expression and function in GBM, MCT1 in particular. Methods: Expression of hypoxia-and glycolytic-related markers, as well as MCT1 and MCT4 isoforms was assessed in in vitro and in vivo orthotopic glioma models, and also in human GBM tissues by immunofluorescence/immunohistochemistry and Western blot. Following MCT1 inhibition, either pharmacologically with CHC (a-cyano-4-hydroxynnamic acid) or genetically with siRNAs, we assessed GBM cell viability, proliferation, metabolism, migration and invasion, under normoxia and hypoxia conditions. Results: Hypoxia induced an increase in MCT1 plasma membrane expression in glioma cells, both in in vitro and in vivo models. Additionally, treatment with CHC and downregulation of MCT1 in glioma cells decreased lactate production, cell proliferation and invasion under hypoxia. Moreover, in the in vivo orthotopic model and in human GBM tissues, there was extensive co-expression of MCT1, but not MCT4, with the GBM hypoxia marker CAIX. Conclusion: Hypoxia-induced MCT1 supports GBM glycolytic phenotype, being responsible for lactate efflux and an important mediator of cell survival and aggressiveness. Therefore, MCT1 constitutes a promising therapeutic target in GBM., This study was supported by Projecto Estratégico- LA 26 – 2013-2014 (PEst-C/SAL/LA0026/2013) and ON.2 SR&TD Integrated Program (NORTE-07-0124FEDER-000017)” co-funded by Programa Operacional Regional do Norte (ON.2- O Novo Norte), Quadro de Referência Estratégico Nacional (QREN), through Fundo Europeu de Desenvolvimento Regional (FEDER), as well as MCTI/CNPq Nº 73/2013 (Brazil). VMG received a fellowship from Fundação para a Ciência e Tecnologia (FCT) ref. SFRH/BD/51997/2012., info:eu-repo/semantics/publishedVersion

I. Bodi, R. Selway, P. Bannister, L. Doey, N. Mullatti, R. Elwes and M. Honavar (2012) Neuropathology and Applied Neurobiology38, 411–425 Diffuse form of dysembryoplastic neuroepithelial tumour: the histological and immunohistochemical features of a distinct entity showing transition to dysembryoplastic neuroepithelial tumour and ganglioglioma Aims: A diffuse variant of dysembryoplastic neuroepithelial tumour (dDNT) has previously been described, which although composed of oligodendroglia-like cells (OLC), astrocytes and mature neurones, lacks the multinodularity and ‘specific component’ of typical DNT. The dDNT poses a significant challenge to the neuropathologist. This study was undertaken to further characterize the histological and immunohistochemical features of dDNT. Materials and methods: Review of our archived material from epilepsy surgery identified 16 cases, in which features of dDNT predominated. Their histological and immunohistochemical features, including CD34 and nestin immunohistochemistry, were analysed. Results: Seven cases had the characteristics of pure dDNT. A further two cases of dDNT showed extension into the white matter with occasional dysplastic neurones. Two additional cases had similar features but with the presence of either single, or multiple small nodular clusters of OLC, in keeping with transition to classical DNT. Five cases showed ganglioglioma-like areas, of which three cases had micronodule formation but with predominant dDNT pattern. In all the cases the dDNT areas showed strong CD34 and less intense nestin immunoreactivity and microglial activation highlighting the full extent of the lesions. There was variable overlap between CD34 and nestin positivity within the micronodular and/or ganglioglioma-like areas. Conclusions: Immunoreactivity for CD34 and nestin characterizes the dDNT and helps to distinguish it from other lesions associated with epilepsy. Histological evidence indicative of transition of dDNT to other forms of DNT and ganglioglioma suggests that dDNT might be an early histogenetic form of these glioneuronal tumours.

Resumo: Os sarcomas primários do pulmão são neoplasias raras e potencialmente agressivas, que devem ser distinguidos de outros tumores pulmonares malignos e cujo comportamento biológico não está completamente esclarecido.Os autores apresentam um caso clínico de sarcoma pleomórfico indiferenciado do pulmão, que foi diagnosticado a um homem de 66 anos. Na altura do diagnóstico foi realizada desobstrução brônquica por laser e radioterapia, tendo sido posteriormente observada uma sobrevivência superior a 11 anos. Abstract: Primary sarcomas of the lung are uncommon, potentially aggressive neoplasms that need to be distinguished from other malignant pulmonary tumors and whose biological behavior is as yet not fully understood.Primary undifferentiated pleomorphic sarcoma was diagnosed in the right lung of a 66 year-old man, who has survived over 11 years after treatment with endobronchial tumor debulking by laser therapy and radiotherapy. Palavras-chave: Neoplasias pulmonares, Sarcoma pulmonar, Sarcoma pleomórfico indiferenciado pulmonar, Sobrevivência prolongada, Keywords: Lung neoplasm, Pulmonary sarcoma, Undifferentiated pleomorphic pulmonary sarcoma, Long survivors

Primary sarcomas of the lung are uncommon, potentially aggressive neoplasms that need to be distinguished from other malignant pulmonary tumors and whose biological behavior is as yet not fully understood.Primary undifferentiated pleomorphic sarcoma was diagnosed in the right lung of a 66 year-old man, who has survived over 11 years after treatment with endobronchial tumor debulking by laser therapy and radiotherapy. Resumo: Os sarcomas primários do pulmão são neoplasias raras e potencialmente agressivas, que devem ser distinguidos de outros tumores pulmonares malignos e cujo comportamento biológico não está completamente esclarecido.Os autores apresentam um caso clínico de sarcoma pleomórfico indiferenciado do pulmão, que foi diagnosticado a um homem de 66 anos. Na altura do diagnóstico foi realizada desobstrução brônquica por laser e radioterapia, posteriormente foi observada uma sobrevivência superior a 11 anos. Keywords: Lung neoplasm, Pulmonary sarcoma, Undifferentiated pleomorphic pulmonary sarcoma, Long survivors, Palavras-chave: Neoplasias pulmonares, Sarcoma pulmonar, Sarcoma pleomórfico indiferenciado pulmonar, Sobrevivência prolongada

Two new cases of extraventricular neurocytoma are reported. The first concerns an 18-year-old female with a left frontal lobe lesion and the second occurred in a 54-year-old female in the thoracic spinal cord. The first patient is free of disease after 18 months of follow up. The second patient is stable after 16 months of follow up. Both were operated - total excision in Case 1 and partial resection in Case 2. The latter underwent adjuvant radiotherapy due to atypical histological features. Cases of extraventricular neurocytoma are reviewed. Differences and similarities between extraventricular and central neurocytoma are outlined.

Osteoblastoma is an uncommon benign bone tumor that accounts for 1% of all primary bone tumors. Well documented in the spine and long bones, it is rarely found in the skull, namely in the sphenoid bone, with only five cases reported in the literature. We report a case of an 11-year-old girl with a histologically confirmed benign osteoblastoma in an unusual location and an atypical aspect on the imaging studies.

A colite microscópica é uma entidade que engloba a colite colagenosa e a colite linfocítica e é actualmente considerada uma causa comum de diarreia crónica que, apesar de benigna, tem um impacto significativo na qualidade de vida dos doentes. O diagnóstico é exclusivamente histológico. Uma vez que a colite microscópica foi descrita pela primeira vez em 1976 e apenas recentemente foi reconhecida como uma causa comum de diarreia, existem ainda muitos clínicos não sensibilizados para esta entidade. Descrevemos o caso de um doente com diarreia crónica aquosa, inicialmente sem repercussão sistémica significativa e com exames laboratoriais e imagiológicos normais ou inconclusivos, mas que evoluiu para um quadro de choque com disfunção renal grave. Alertamos para o facto de que deverá haver uma maior insistência, por parte dos clínicos, na realização de biópsias de forma a estabelecer o correcto diagnóstico e a instituição de terapêutica adequada. Microscopic colitis is a disorder that includes collagenous colitis and lymphocytic colitis. It is considered to be a common cause of chronic diarrhea. Although it is benign, it can have a significant impact on the patient's quality of life. The diagnosis is exclusively histological. Although microscopic colitis was first described in 1976, it has only recently been recognized as a common cause of diarrhea. Many clinicians are not yet aware of this entity. We present the case a patient with chronic watery diarrhea, initially without significant systemic repercussions and with normal or inconclusive laboratory or imaging tests. This evolved into hypovolemic shock with severe renal dysfunction. Greater awareness of this condition by clinicians, leading to the performance of timely biopsies, required for the correct diagnosis and appropriate therapy, is required.

Human hotspot TERT promoter (TERTp) mutations have been reported in a wide range of tumours. Several studies have shown that TERTp mutations are associated with clinicopathological features; in some instances, TERTp mutations were considered as biomarkers of poor prognosis. The rs2853669 SNP, located in the TERT promoter region, was reported to modulate the increased TERT expression levels induced by the recurrent somatic mutations. In this study we aimed to determine the frequency and prognostic value of TERTp mutations and TERT rs2853669 SNP in 504 gliomas from Portuguese and Brazilian patients. TERTp mutations were detected in 47.8% of gliomas (216/452). Glioblastomas (GBM) exhibited the highest frequency of TERTp mutations (66.9%); in this glioma subtype, we found a significant association between TERTp mutations and poor prognosis, regardless of the population. Moreover, in a multivariate analysis, TERTp mutations were the only independent prognostic factor. Our data also showed that the poor prognosis conferred by TERTp mutations was restricted to GBM patients carrying the rs2853669 A allele and not in those carrying the G allele. In conclusion, the presence of TERTp mutations was associated with worse prognosis in GBM patients, although such association depended on the status of the rs2853669 SNP. The status of the rs2853669 SNP should be taken in consideration when assessing the prognostic value of TERTp mutations in GBM patients. TERTp mutations and the rs2853669 SNP can be used in the future as biomarkers of glioma prognosis.

Summary Background Abnormal late responses to single pulse electrical stimulation (SPES) in patients with intracranial recordings can identify epileptogenic cortex. We aimed to investigate the presence of neuropathological abnormalities in abnormal SPES areas and to establish if removal of these areas improved postsurgical seizure control. Methods We studied abnormal responses to SPES during chronic intracranial recordings in 40 consecutive patients who were thereafter operated on because of refractory epilepsy and had a follow-up period of at least 12 months. Findings 22 patients had abnormal responses to SPES exclusively located in resected regions (96% with favourable outcome), seven had abnormal responses to SPES located in resected and non-resected regions (71% with favourable outcome), three had abnormal responses to SPES exclusively outside the resected region (none with favourable outcome), and eight did not have abnormal responses to SPES (62·5% with favourable outcome). Surgical outcome was significantly better when areas with abnormal responses to SPES were completely resected compared with partial or no removal of abnormal SPES areas (p=0·006). Neuropathological examination showed structural abnormalities in the abnormal SPES areas in 26 of the 29 patients in whom these regions were resected, despite the absence of clear MRI abnormalities in nine patients. Interpretation Abnormal responses to SPES are functional markers of epileptogenic structural abnormalities, and can identify epileptogenic cortex and predict surgical outcome, especially when a frontal or temporal focus is suspected.

Reductions in neuronal size and glial cell density have been described in the frontal cortex in major psychiatric disorders. In this investigation, we performed a cytoarchitectural assessment within the planum temporale (PT), an auditory association region located within the superior temporal gyrus, using two-dimensional (2D) measures of cell size and density and spatial point pattern analysis. In sections of the PT from subjects with schizophrenia, bipolar disorder, major depressive disorder and controls (15 subjects per group), the laminar distribution and size of all neurons and glial cell nuclei was recorded. Spatial point pattern investigation demonstrated reduced neuronal clustering in bipolar disorder (p=0.033) and schizophrenia (p=0.027) compared with controls. Statistical analyses comparing each of the patient groups with the control group failed to identify differences in neuronal density between groups. Neuronal size was reduced in cortical layer 3 (p=0.02) and glial cell density reduced in cortical layer 6 (p=0.05) in bipolar disorder relative to controls but these findings did not remain significant after adjusting for six layer-wise comparisons. We propose that alterations in cortical cytoarchitecture within this region are subtle and involve reduced clustering of neurons, which may be due to altered neuronal organisation within cortical mini-columns or within cortical layers.

C cell hyperplasia is associated with medullary carcinoma of the thyroid in the inherited MEN2 syndromes, in which the great majority of cases have been shown to be due to a mutation in the RET oncogene. We report a study of a family with C cell hyperplasia and hypercalcitoninemia in which no cases of medullary carcinoma have yet occurred and which lacked an identifiable causative RET mutation. Four of the family members showed hypercalcitoninemia, and marked C cell hyperplasia was present in each of the three in whom thyroidectomy has been performed. We investigated the possible involvement of the SDHD gene, because somatic and germline mutations in this gene have been found in a variety of tumors of neural crest-derived tissue. A germline mutation in exon 2 of the SDHD gene (c149 A-G, His 50 Arg) was found in six members of the family; all the four available members with hypercalcitoninemia possessed the mutation. One of the five available members without hypercalcitoninemia, an 18-yr-old female, also showed the mutation. We conclude that we have identified a new syndrome, characterized by familial non-RET C cell hyperplasia. Our studies suggest that a mutation in SDHD may be causative. These observations have implications for apparently incidental cases of hypercalcitoninemia or C cell hyperplasia.

Summary: Purpose: Hamartomas of the hypothalamus (HH) cause an uncommon and unusual epilepsy syndrome. The condition is recognized to affect children, but the presentation in adults is not well understood. We present 19 children and adult patients with HH, including three patients whose epilepsy began in adult life. The patterns of clinical presentation, evolution of the epilepsy from childhood to adult life, and electroclinical diagnostic features are presented. Methods: Nineteen patients, both children and adults with HH and epilepsy, were evaluated clinically, with EEG, videoEEG, and magnetic resonance imaging (MRI) scanning. Seven patients underwent surgical resection of the hamartoma. Stereotactic thermocoagulation of the hamartoma was performed in two patients. Results: Gelastic seizures occurred at onset of epilepsy in 15 of 16 early-onset cases. Subsequently, multiple seizures types occurred, which then evolved to mainly partial epilepsy with tonic or complex partial seizures (five of eight adults), or became entrenched symptomatic generalized epilepsy with atypical absences, drop attacks, and secondarily generalized seizures, and cognitive impairment (three of eight adults). In the adult-onset patients, gelastic seizures were not prominent, the epilepsy was milder, and they functioned normally. Stereotactic thermocoagulation of the hamartoma resulted in improvement in seizure control in two patients. Conclusions: Gelastic seizures are not a prominent feature of epilepsy in adult patients with HH. The epilepsy associated with HH, although severe at onset, can evolve into a milder syndrome in later life. For less severely affected patients, minimally invasive alternatives to the traditionally difficult open surgical treatment should be considered. Key Words: Hypothalamus hamartoma—Gelastic seizures—Precocious puberty— Stereotactic thermocoagulation.

INTRODUÇÃO E OBJETIVO: Descrição das características demográficas, clinicas e neuropatológicas de 11 doentes com doença de Creutzfeldt-Jakob (DCJ). MÉTODO: Revisão clínica e neuropatológica de doentes com DCJ diagnosticados entre 1993 e 2002 em hospitais do Norte de Portugal. RESULTADOS: Foram identificados 11 doentes (4 do sexo feminino; idade média de início dos sintomas, 64 anos; média de duração da doença, 8 meses). Todos apresentaram síndrome demencial progressiva associada a mioclonias, sendo a síndrome cerebelar a forma de apresentação inicial em quatro deles. O estudo neuropatológico revelou sempre espongiose e gliose reativa associada a perda neuronal. O estudo imunocitoquímico para proteína priônica (PrP) foi positivo nos oito casos em que foi executado. CONCLUSÃO: O grupo de doentes descritos constitui uma série clinica representativa da heterogeneidade de fenótipos possíveis da DCJ esporádica. O estudo neuropatológico é ainda indispensável para o diagnóstico definitivo da doença. OBJECTIVE: Description of the demographic, clinical and neuropathological features of 11 cases of Creutzfeldt-Jakob disease (CJD). METHOD: Review of the clinical and neuropathological features of patients with CJD diagnosed in hospitals in the North of Portugal between 1993 and 2002. RESULTS: Eleven patients were identified, 4 females: mean age of onset of symptoms - 64 years, mean duration of disease - 8 months. All presented with a syndrome of progressive dementia with myoclonus, with four patients presenting with cerebellar signs. Neuropathological examination of brain at autopsy showed spongiosis and reactive gliosis associated with neuronal loss. In eight cases immunocytochemistry for prion protein (PrP) was carried out and was positive. CONCLUSION: The group of patients described represents the heterogeneity of the clinical phenotypes possible in CJD. Neuropathological examination is still indispensable to make the definitive diagnosis of the disease.

The pattern of cell loss and changes in the expression of inhibitory and excitatory receptors in the subzones of the hippocampus in patients with pharmacoresistant (drug-refractory) complex partial seizures was studied. Neuronal densities were measured in the mid-hippocampus in temporal lobectomy (n = 10) and total hemispherectomy (n = 2) specimens from 12 patients with mesial temporal sclerosis (MTS), in temporal lobectomy (n = 6) and hemispherectomy (n = 5) samples from 11 epileptic patients without MTS, and in six autopsy brains from patients without neurological disease. No differences in hippocampal cell densities were found between the autopsy and the non-MTS group. The MTS group, compared with the non-MTS or the autopsy group, showed a 95% decrease in neuronal density in CA1, a 70% decrease in cornu ammonis (CA)2, an 85% decrease in CA3, and an 80% decrease in CA4. The proportion of neurons staining positively with a polyclonal antibody for the α-amino-3-hydroxy-5-methyl-4-isoxazole proprionic acid (AMPA) glutamate receptor subunits GluR2 and GluR3 was increased to 32% in the CA1 region in the MTS group, compared with 21% in the non-MTS hippocampi. This difference was, however, just at the level of statistical significance (P = 0.054). Elsewhere in the hippocampus no significant change was observed. By contrast, the proportion of cells staining positively with a monoclonal antibody to the β-subunit of the GABAA benzodiazepine (BZ) receptor was markedly increased in the MTS hippocampi, from 13% in non-MTS CA1 to 50% in MTS CA1 region; and from 26% in non-MTS CA3 to 63% in MTS CA3. Although previous studies (in vivo and ex vivo) have emphasized a loss of BZ receptors in temporal lobe epilepsy, this study shows that the expression of the GABAA receptor immunopositive population appears to be increased relative to the neuronal density.

Focal cortical dysplasia (FCD) is a rare, sporadic disorder which is a recognised cause of chronic epilepsy. It is proposed to result from disordered neuronal migration and differentiation and has characteristic histological features which include disturbed cortical lamination, large abnormal neurons and the presence of large balloon cells with glassy eosinophilic cytoplasm and pleomorphic eccentric nuclei. These latter express both glial and neuronal markers indicative of abnormal neuroglial differentiation. In this paper we review the current literature on the neuropathology of FCD and discuss potential mechanisms. We focus on growth factors, signalling pathways and candidate genes with known roles in Drosophila and vertebrate brain development that could be responsible for the developmental brain changes seen in FCD. At issue are the factors that influence cell fate and differentiation and which regulate neural migration. Some of the molecular pathways, such as those involving the Notch and the Wnt pathways have particularly important roles in neuroglial differentiation in vertebrates, and these are proposed as potential candidates.

A cavernous malformation involving the Gasserian ganglion, 2nd and 3rd divisions of the trigeminal nerve on the left side was resected via an extradural route in a 54 year old male. Cavernous malformations of the cranial nerves are rare. Specific origin from the trigeminal nerve has not been previously reported.

An unusual multinodular and vacuolating neuronal tumour (MVNT) has been described in the cerebral hemispheres of ten patients with adult-onset seizures. We report the findings in two cases with similar features, a surgical resection and the other an autopsy specimen. Case 1, a 34-year-old female, underwent surgical resection for a multinodular non-enhancing frontal white matter lesion causing intractable epilepsy. Case 2, presented with motor neurone disease (MND) at the age of 71 and MRI scanning revealed extensive multinodular non-enhancing white matter lesions in the temporal lobe. There was no history of epilepsy and post mortem histology confirmed MND. Macroscopically multiple small grey well-formed, discrete and coalescent nodules were seen in the deep cortex and subcortical white matter. On histology, mature-looking neurons with large cytoplasmic vacuoles were distributed in a fibrillary background, where vacuoles were also noted. In the resected tumour scattered oligodendroglia-like cells were present. No ganglion cells were seen. The vacuolated cells exhibited immunopositivity for synaptophysin, HuC/HuD and p62 but were negative for NeuN, neurofilament, GFAP, IDH1, nestin and CD34. Electron microscopy showed non-membrane bound cytoplasmic vacuoles in the neurons and in some neuronal processes. The seizures recurred in Case 1. Some clinicopathological features of this lesion suggest a possible relationship with dysembryoplastic neuroepithelial tumour (DNT) although the morphological features are not typical of DNT. Case 2 demonstrates that MVNT may remain asymptomatic.

MGMT downregulation in high-grade gliomas (HGG) has been mostly attributed to aberrant promoter methylation and is associated with increased sensitivity to alkylating agent-based chemotherapy. However, HGG harboring 10q deletions also benefit from treatment with alkylating agents. Because the MGMT gene is mapped at 10q26, we hypothesized that both epigenetic and genetic alterations might affect its expression and predict response to chemotherapy. To test this hypothesis, promoter methylation and mRNA levels of MGMT were determined by quantitative methylation-specific PCR (qMSP) or methylation-specific multiplex ligation dependent probe amplification (MS-MLPA) and quantitative RT-PCR, respectively, in a retrospective series of 61 HGG. MGMT/chromosome 10 copy number variations were determined by FISH or MS-MLPA analysis. Molecular findings were correlated with clinical parameters to assess their predictive value. Overall, MGMT methylation ratios assessed by qMSP and MS-MLPA were inversely correlated with mRNA expression levels (best coefficient value obtained with MS-MLPA). By FISH analysis in 68.3% of the cases there was loss of 10q26.1 and in 15% of the cases polysomy was demonstrated; the latter displayed the highest levels of transcript. When genetic and epigenetic data were combined, cases with MGMT promoter methylation and MGMT loss depicted the lowest transcript levels, although an impact in response to alkylating agent chemotherapy was not apparent. Cooperation between epigenetic (promoter methylation) and genetic (monosomy, locus deletion) changes affecting MGMT in HGG is required for effective MGMT silencing. Hence, evaluation of copy number alterations might add relevant prognostic and predictive information concerning response to alkylating agent-based chemotherapy.

Background. Gliomas exhibit high glycolytic rates, and monocarboxylate transporters (MCTs) play a major role in the maintenance of the glycolytic metabolism through the proton-linked transmembrane transport of lactate. However, their role in gliomas is poorly studied. Thus, we aimed to characterize the expression of MCT1, MCT4, and their chaperone CD147 and to assess the therapeutic impact of MCT inhibition in gliomas. Methods. MCTs and CD147 expressions were characterized by immunohistochemistry in nonneoplastic brain and glioma samples. The effect of CHC (MCT inhibitor) and MCT1 silencing was assessed in in vitro and in vivo glioblastoma models. Results. MCT1, MCT4, and CD147 were overexpressed in the plasma membrane of glioblastomas, compared with diffuse astrocytomas and nonneoplastic brain. CHC decreased glycolytic metabolism, migration, and invasion and induced cell death in U251 cells (more glycolytic) but only affected proliferation in SW1088 (more oxidative). The effectiveness of CHC in glioma cells appears to be dependent on MCT membrane expression. MCT1 downregulation showed similar effects on different glioma cells, supporting CHC as an MCT1 inhibitor. There was a synergistic effect when combining CHC with temozolomide treatment in U251 cells. In the CAM in vivo model, CHC decreased the size of tumors and the number of blood vessels formed. Conclusions. This is the most comprehensive study reporting the expression of MCTs and CD147 in gliomas. The MCT1 inhibitor CHC exhibited anti-tumoral and anti-angiogenic activity in gliomas and, of importance, enhanced the effect of temozolomide. Thus, our results suggest that development of therapeutic approaches targeting MCT1 may be a promising strategy in glioblastoma treatment., This work was supported by the Life and Health Sciences Research Institute, University of Minho, Portugal, and Fundação para a Ciência e Tecnologia 845 (SFRH/BI/33503/2008 to V.M.G., SFRH/BPD/ 69479/2010 to C.P., and SFRH/BD/36463/2007 to O.M.).

The gene encoding protein kinase WNK2 was recently identified to be silenced by promoter hypermethylation in gliomas and meningiomas, suggesting a tumour-suppressor role in these brain tumours. Following experimental depletion in cell lines, WNK2 was further found to control GTP-loading of Rac1, a signalling guanosine triphosphatase involved in cell migration and motility. Here we show that WNK2 promoter methylation also occurs in 17.5 (29 out of 166) of adult gliomas, whereas it is infrequent in its paediatric forms (1.6; 1 out of 66). Re-expression of WNK2 in glioblastoma cells presenting WNK2 gene silencing reduced cell proliferation in vitro, tumour growth in vivo and also cell migration and invasion, an effect correlated with reduced activation of Rac1. In contrast, when endogenous WNK2 was depleted from glioblastoma cells with unmethylated WNK2 promoter, changes in cell morphology, an increase in invasion and activation of Rac1 were observed. Together, these results validate the WNK2 gene as a recurrent target for epigenetic silencing in glia-derived brain tumours and provide first mechanistic evidence for a tumour-suppressing role of WNK2 that is related to Rac1 signalling and tumour cell invasion and proliferation., This work was supported by the Portuguese Fundacao para a Ciencia e Tecnologia (grant PTDC/SAU-OBD/100079/2008 to P.J., grants PTDC/SAU-IMU/110303/2009 and PTDC/SAU-MII/100780/2008 to L. F. M. and PEst-OE/BIA/UI4046/2011 to the BioFig research unit; fellowships SFRH/BD/36463/2007 to O.M. and UMINHO/BI/016/2011 to F. P.). L. F. M. receives support from Fundacao Luso-Americana para o Desenvolvimento and C.J. acknowledges NHS funding to the Biomedical Research Centre.