The Challenge of Somatic Variants in Focal Cortical Dysplasia

Objective

The advent of next-generation sequencing (NGS) enabled the detection of low-level brain somatic variants in postsurgical tissue of focal cortical dysplasia (FCD). The genetic background of FCD Type I remains elusive, while the mammalian target of rapamycin (mTOR) pathway seems to have a relevant role in the pathogenesis of FCD Type II. Our goal was to uncover information on the molecular basis of FCD, performing whole genome sequencing (WGS) in postsurgical tissue to detect candidate brain-specific somatic variants, and evaluate their clinical significance.

Design

WGS was performed using paired peripheral venous blood and postsurgical pathological brain deoxyribonucleic acid (DNA) samples. Libraries were prepared using the Roche KAPA HyperPrep polymerase chain reaction (PCR) free library preparation kit. Paired-end 150bp reads were generated on the Illumina NovaSeq platform. The FASTQ files were processed using the nf-core sarek pipeline (version 3.0) to call somatic variants, which were then annotated with ANNOVAR. A screening strategy was applied to obtain relevant variants.

Results

Two female patients with drug-resistant epilepsy due to FCD who underwent surgical treatment were included. Regarding neuropathological diagnosis, one patient had FCD Type Ia and the other had FCD Type IIa. Five somatic nonsynonymous single nucleotide variants (SNVs) were detected using WGS, three in FCD Ia tissue (WDR24 p.Trp259Gly; MICAL1 p.Lys1036Arg; and KATNB1 p.Leu566Ile) and two in FCD IIa tissue (MATN4 p.Phe91Val and ANKRD6 p.His386Gln). All variants were predicted to be potentially pathogenic by at least two different tools. However, they were classified as variants of uncertain significance (VUS) according to the American College of Medical Genetics and Genomics (ACMG) criteria.

Conclusion

Brain-specific somatic missense variants were identified by NGS in new candidate genes (WDR24, MICAL1, KATNB1, MATN4, and ANKRD6) using postsurgical FCD tissue, which may contribute to further understanding of the genetic background of FCD. All the reported genes were previously related to epilepsy and/or malformations of central nervous system (CNS) and cortical development. However, the pathogenicity assessment of these variants and, consequently, their impact on clinical practice still poses an important challenge.

An Immunohistochemical Study of Breast Cancer Brain Metastases: The Role of CD44 and AKT in the Prognosis

Breast cancer is a major health burden, and up to one-third of patients with breast cancer develop brain metastases, which are linked to a very poor prognosis. Few biomarkers are available to predict the prognosis of patients with metastases. Assessment by immunohistochemistry may be used as a tool to predict the behavior of these tumors. A retrospective transversal study including 114 patients (diagnosed between 2000 and 2016) with breast cancer brain metastases was carried out using archival biological material from 114 patients with breast cancer brain metastases. Expression of CD44, HER2, ER, PR, CA9, PDL-1, CD133, ALDH1, PTEN, AKT, PI3K, and AR markers was assessed by immunohistochemistry. The overexpression of CD44 and AKT was associated with worse overall survival ( P =0.047 and P =0,034, respectively), on univariate analysis, in the cohort of parenchymal and bone metastases; the impact of AKT expression was also evident in the parenchymal cohort on uni ( P =0.021) and multivariate analysis ( P =0.027). The remaining markers did not exhibit a statistical correlation. Immunohistochemistry markers such as CD44 and AKT may have a prognostic impact on survival in patients with breast cancer brain metastases. The conjugation with other markers may help with the stratification of patients and therapy.

Resective Epilepsy Surgery and Respective Histopathological Diagnoses: A Retrospective Cohort Study

INTRODUCTION

Over recent decades, brain resection for drug-resistant epilepsy has proven to be a valuable treatment option. The histopathological classification was of paramount value for patient management. The aims of this study were to characterize our resective epilepsy surgical series including the histopathological diagnoses and to understand the differences in clinical practice between two different periods of our epilepsy surgical programme.

MATERIAL AND METHODS

We performed a retrospective cohort study, including patients with drug-resistant epilepsy that underwent resective surgery between 1997 and 2021 in the Coimbra University Hospital Centre. Histopathological diagnoses were classified into seven major conventional categories. For comparison purposes, the cohort was divided into two consecutive periods of 12 years.

RESULTS

A total of 259 patients were included, from which 228 (88%) were adults at the time of surgery. The median disease duration prior to surgery was 14 (interquartile range 23) years. Fifty-five (21%) patients performed pre-surgical invasive work-up. The temporal lobe was the most frequently operated region (73%). Major and minor post-surgical complications were identified in 21 (8%) patients. A reduction in the number of antiepileptic drugs was possible in 96 (37%) patients after surgery. The most common histopathological diagnosis was hippocampal sclerosis, but among children it was long-term epilepsy associated tumour. Long-term epilepsy associated tumours, hippocampal sclerosis and vascular malformations had the best post-operative outcomes. Malformations of cortical development and glial scars had the worst outcomes. Regarding differences between the two periods, the absolute number of operated patients increased (119 versus 140), and the age at surgery was higher in the second period (p = 0.04). The number of malformations of cortical development increased (p = 0.01), but the number of other tumours (p = 0.01) and specimens with no lesion (p = 0.03) decreased in the same period.

CONCLUSION

This study is in line with contemporaneous research, reinforcing the previous knowledge on the underlying structural aetiologies, clinical practice, and surgical outcomes over more than two decades of experience. Our data provide realistic expectations about epilepsy surgery and highlight the need for further improvements in diagnosis and treatment paradigm for people with chronic epilepsy.

The landscape of common genetic drivers and DNA methylation in low-grade (epilepsy-associated) neuroepithelial tumors: A review

Low-grade neuroepithelial tumors (LNETs) represent an important group of central nervous system neoplasms, some of which may be associated to epilepsy. The concept of long-term epilepsy-associated tumors (LEATs) includes a heterogenous group of low-grade, cortically based tumors, associated to drug-resistant epilepsy, often requiring surgical treatment. LEATs entities can sometimes be poorly discriminated by histological features, precluding a confident classification in the absence of additional diagnostic tools. This study aimed to provide an updated review on the genomic findings and DNA methylation profiling advances in LNETs, including histological entities of LEATs. A comprehensive search strategy was conducted on PubMed, Embase, and Web of Science Core Collection. High-quality peer-reviewed original manuscripts and review articles with full-text in English, published between 2003 and 2022, were included. Results were screened based on titles and abstracts to determine suitability for inclusion, and when addressed the topic of the review was screened by full-text reading. Data extraction was performed through a qualitative content analysis approach. Most LNETs appear to be driven mainly by a single genomic abnormality and respective affected signaling pathway, including BRAF p.V600E mutations in ganglioglioma, FGFR1 abnormalities in dysembryoplastic neuroepithelial tumor, MYB alterations in angiocentric glioma, BRAF fusions in pilocytic astrocytoma, PRKCA fusions in papillary glioneuronal tumor, between others. However, these molecular alterations are not exclusive, with some overlap amongst different tumor histologies. Also, clustering analysis of DNA methylation profiles allowed the identification of biologically similar molecular groups that sometimes transcend conventional histopathological classification. The exciting developments on the molecular basis of these tumors reinforce the importance of an integrative histopathological and (epi)genetic classification, which can be translated into precision medicine approaches.

HGG-55. An adolescent with a High-Grade Glioma: persuing a specific diagnosis

BACKGROUND: Recognizing the value of molecular parameters provides evidence with repercussions on diseases classification. CLINICAL CASE: A thirteen-year-old girl was admitted in coma at the Intensive Care Unit due to a hemorrhagic stroke. CT revealed an expansive left frontal lobe lesion with perilesional edema and compression signs by an extensive hematoma. She underwent an emergency decompressive craniotomy for hematoma drainage, and the lesion was biopsied. The subsequent MRI showed a large heterogeneous mass with a cystic component. A first subtotal resection of the lesion was performed considering the language area. The histopathological examination showed tumor cells organized in perivascular pseudorosettes around the central hyalinized thickened blood vessel throughout the tumor, a pattern typically encountered in astroblastoma. Immunochemistry stains revealed a positive reactivity for GFAP, Olig2, and synaptophysin. The molecular study found a BRAFV600E mutation and homozygous CDKN2A e CDKN2B deletions; no TERT amplification, BCORL1, nor MN1 gene rearrangements were identified. She completed six weeks of radiotherapy without neurological signs/symptoms. A new surgical intervention was done 12 weeks later due to a slight increase of residual lesion. The rapid growth and the presence of viable tumor cells justified the therapy with irinotecan and bevacizumab, with mild adverse effects. One year after diagnosis, the adolescent is clinically well, without neurologic deficits and the MRI without evidence of residue or tumor recurrence. DISCUSSION: We began therapy based on morphological diagnosis. Complete resection and radiotherapy proved to be beneficial as in other high-grade gliomas, but the value of other therapies is still unknown. The BRAF gene variant would allow treatment with dabrafenib (in association with trametinib) or vemurafenib; however, she presents molecular findings associated with poor prognosis (CDKN2A deletion) that may impair the effectiveness of these therapies. According to the new WHO classification, the absence of MN1 alterations precludes the diagnosis of astroblastoma.

Cytogenomic Analysis of Long-Term Epilepsy-Associated Tumors Using an Array-Based CGH Strategy

A palette of copy number changes in long-term epilepsy-associated tumors (LEATs) have been reported, but the data are heterogeneous. To better understand the molecular basis underlying the development of LEATs, we performed array-comparative genomic hybridization analysis to investigate chromosomal imbalances across the entire genome in 8 cases of LEATs. A high number of aberrations were found in 4 patients, among which deletions predominated. Both whole-chromosome and regional abnormalities were observed, including monosomy 19, deletion of 1p, deletions of 4p, 12p, and 22q, and gain of 20p. The common altered regions are located mainly on chromosomes 19 and 4p, identifying genes potentially involved in biological processes and cellular mechanisms related to tumorigenesis. Our study highlights new genomic alterations and reinforces others previously reported, offering new molecular insights that may help in diagnosis and therapeutic decision-making.

Neurological impact of eosinophilic granulomatosis with polyangiitis

Nervous system (NS) affection may occur in Eosinophilic Granulomatosis with Polyangiitis (EGPA), but its clinical manifestations and pathophysiology are rarely described. Our aims are to characterize central and peripheral NS (CNS/PNS) involvement and compare biological markers in EGPA patients with and without neurological manifestations. Retrospective observational study, including EGPA patients with and without neurological manifestations. Demographics, clinical data, and immunological markers were analyzed. Descriptive and inferential statistics were performed. Sixteen patients were included; 11 (68.8%) of whom were male, with a mean age of 63.38 years; 8 with (Group 1) and 8 without (Group 2) neurological findings. Neurological impairment preceded EGPA diagnosis in 5 patients, and occurred during follow-up in 3 patients after a median of 4.0 years. CNS manifestations observed were stroke (n = 2), bilateral central retinal artery occlusion (n = 1), and compressive dorsal myelopathy due to extradural granulation tissue (n = 1). PNS manifestations were axonal polyneuropathy (n = 3), sensorineural hearing loss (n = 3), and multiplex mononeuropathy (n = 1). Two patients had both PNS and CNS involvement. There were no statistical differences regarding biological markers [eosinophil count, myeloperoxidase (MPO) antibodies titers] between the 2 groups. One patient from Group 1 was unresponsive to treatment and permanent neurological sequelae were observed in 7 cases. EGPA-related NS involvement can be heterogeneous and is responsible for long-term sequelae. In our sample, the main neurological scenarios were peripheral neuropathy, VIII cranial nerve neuropathy, ischemic lesions and compressive myelopathy. Patients with and without neurological manifestations did not differ in eosinophilic count and MPO titer.

MiR-200c-based metabolic modulation in glioblastoma cells as a strategy to overcome tumor chemoresistance

Glioblastoma (GB) is the most aggressive and common form of primary brain tumor characterized by fast proliferation, high invasion, and resistance to current standard treatment. The average survival rate post-diagnosis is 14.6 months, despite the aggressive standard post-surgery radiotherapy concomitant with chemotherapy with temozolomide (TMZ). Currently, efforts are being endowed to develop new and more efficient therapeutic approaches capable to overcome chemoresistance, inhibit tumor progression and improve overall patient survival rate. Abnormal microRNA (miRNA) expression has been correlated with chemoresistance, proliferation and resistance to apoptosis, which result from their master regulatory role of gene expression. Altered cell metabolism, favoring glycolysis, was identified as an emerging cancer hallmark and has been described in GB, thus offering a new target for innovative GB therapies. In this work, we hypothesized that a gene therapy-based strategy consisting of the overexpression of a miRNA downregulated in GB and predicted to target crucial metabolic enzymes might promote a shift of GB cell metabolism, decreasing the glycolytic dependence of tumor cells and contributing to their sensitization to chemotherapy with TMZ. The increase of miR-200c levels in DBTRG cells resulted in downregulation of mRNA of enzymes involved in bioenergetics pathways and impaired cell metabolism and mobility. Additionally, miR-200c overexpression prior to DBTRG cell exposure to TMZ resulted in cell cycle arrest. Overall, our results show that miR-200c overexpression could offer a way to overcome chemoresistance developed by GB cells in response to current standard chemotherapy, providing an improvement to current GB standard treatment, with benefit for patient outcome.

Primary intramedullary spinal-cord lymphoma (PISCL): a rare entity with a challenging diagnosis

Primary intramedullary spinal-cord lymphoma (PISCL) is a rare cause of myelopathy and constitutes only 1% of central nervous system lymphomas. Delay to diagnosis is common due to its rarity, its similarity to other causes of myelopathy and the difficulties in obtaining pathological diagnosis. We report a case of PISCL and discuss the challenges faced on diagnosis, namely the impact of corticosteroids on histological findings, the usefulness of MRI, positron-emission tomography/CT (PET/CT) and repeated lumbar punctures.

World Health Organization Grade III Meningiomas: A Retrospective Study at an Academic Medical Center

BACKGROUND

Meningiomas are the most common primary brain tumors and are generally considered benign. However, a rare subgroup of meningiomas, classified as World Health Organization (WHO) grade III meningiomas, can show extremely aggressive behavior and high rates of recurrence. Despite ongoing research, data on the clinical outcome of this subgroup of meningiomas are still limited.

METHODS

Medical records of patients with WHO grade III meningiomas diagnosed between 2000 and 2018 at the Coimbra University Hospital Center were retrospectively reviewed and several variables of interest and their relation to patients' survival were analyzed.

RESULTS

Of the 26 patients included in the final analysis, 23 had anaplastic meningiomas, 2 had papillary meningiomas, and 1 had a rhabdoid meningioma. Median overall survival and median progression-free survival were 2.45 and 1.22 years, respectively. Overall survival at 1, 2 and 5 years was 73%, 57%, and 35%, respectively. Adjuvant radiotherapy correlated with improved survival for subtotally resected meningiomas but not for gross totally resected meningiomas. There was a trend toward improved overall survival with gross total resection versus subtotal resection, but this difference failed to reach statistical significance.

CONCLUSIONS

This study provides insight into the clinical outcomes of WHO grade III meningiomas and suggests that adjuvant radiotherapy may not be beneficial for patients who underwent gross total resection. This rare subset of meningiomas still portends a devastating prognosis and the impact of extent of resection and adjuvant therapies in these patients needs further clarification.

Genomic and Epigenetic Advances in Focal Cortical Dysplasia Types I and II: A Scoping Review

Introduction: Focal cortical dysplasias (FCDs) are a group of malformations of cortical development that constitute a common cause of drug-resistant epilepsy, often subjected to neurosurgery, with a suboptimal long-term outcome. The past few years have witnessed a dramatic leap in our understanding of the molecular basis of FCD. This study aimed to provide an updated review on the genomic and epigenetic advances underlying FCD etiology, to understand a genotype-phenotype correlation and identify priorities to lead future translational research. Methods: A scoping review of the literature was conducted, according to previously described methods. A comprehensive search strategy was applied in PubMed, Embase, and Web of Science from inception to 07 May 2020. References were screened based on title and abstract, and posteriorly full-text articles were assessed for inclusion according to eligibility criteria. Studies with novel gene variants or epigenetic regulatory mechanisms in patients that underwent epilepsy surgery, with histopathological diagnosis of FCD type I or II according to Palmini's or the ILAE classification system, were included. Data were extracted and summarized for an overview of evidence. Results: Of 1,156 candidate papers, 39 met the study criteria and were included in this review. The advent of next-generation sequencing enabled the detection in resected FCD tissue of low-level brain somatic mutations that occurred during embryonic corticogenesis. The mammalian target of rapamycin (mTOR) signaling pathway, involved in neuronal growth and migration, is the key player in the pathogenesis of FCD II. Somatic gain-of-function variants in MTOR and its activators as well as germline, somatic, and second-hit mosaic loss-of-function variants in its related repressors have been reported. However, the genetic background of FCD type I remains elusive, with a pleomorphic repertoire of genes affected. DNA methylation and microRNAs were the two epigenetic mechanisms that proved to have a functional role in FCD and may represent molecular biomarkers. Conclusion: Further research into the possible pathogenic causes of both FCD subtypes is required, incorporating single-cell DNA/RNA sequencing as well as methylome and proteomic analysis. The collected data call for an integrated clinicopathologic and molecular genetic diagnosis in current practice not only to improve diagnostic accuracy but also to guide the development of future targeted treatments.

Downregulation of long non-protein coding RNA MVIH impairs glioblastoma cell proliferation and invasion through an miR-302a-dependent mechanism

Glioblastoma (GB) is the most frequent and malignant type of brain tumor, for which no effective therapy exists. The high proliferative and invasive nature of GB, as well as its acquired resistance to chemotherapy, makes this type of cancer extremely lethal shortly after diagnosis. Long non-protein coding RNAs (lncRNA) are a class of regulatory RNAs whose levels can be dysregulated in the context of diseases, unbalancing several physiological processes. The lncRNA associated with microvascular invasion in hepatocellular carcinoma (lncRNA-MVIH), overexpressed in several cancers, was described to co-precipitate with phosphoglycerate kinase 1 (PGK1), preventing secretion of this enzyme to the extracellular environment and promoting cell migration and invasion. We hypothesized that, by silencing the expression of lncRNA-MVIH, the secretion of PGK1 would increase, reducing GB cell migration and invasion capabilities. We observed that lncRNA-MVIH silencing in human GB cells significantly decreased glycolysis, cell growth, migration, and invasion and sensitized GB cells to cediranib. However, no increase in extracellular PGK1 was observed as a consequence of lncRNA-MVIH silencing, and therefore, we investigated the possibility of a mechanism of miRNA sponge of lncRNA-MVIH being in place. We found that the levels of miR-302a loaded onto RISC increased in GB cells after lncRNA-MVIH silencing, with the consequent downregulation of several miR-302a molecular targets. Our findings suggest a new mechanism of action of lncRNA-MVIH as a sponge of miR-302a. We suggest that lncRNA-MVIH knockdown may be a promising strategy to address GB invasiveness and chemoresistance, holding potential towards its future application in a clinical context.

Tumefactive demyelinating lesions spectrum disorders and the potential role of contemporary disease modifying treatments: a case report

Marburg disease is a fulminant variant of multiple sclerosis (MS), in which the diagnosis may be particularly difficult and with high rates of mortality. We describe the case of a women with a clinical picture, radiographic features, and neuropathological findings consistent with the classical descriptions of Marburg disease. Initially, our patient did not improved with the acute phase treatments but later showed a good response to natalizumab (NTZ) treatment. This report highlights not only the utility of brain biopsy in the accurate diagnosis of this challenging condition but also the potential role of NTZ as an effective therapeutic option.

Management and Outcome of Solitary Spinal Amyloidoma-A Systematic Literature Review

BACKGROUND

Solitary spinal amyloidoma (SSA) is a rare and poorly characterized disease. There are few cases described, and the knowledge of this neoplasm is limited. A more accurate description of demographics, clinical findings, and outcomes may be useful for a better understanding of this pathology, as well as therapeutic intervention, adding value to the research of localized amyloidosis.

METHODS

A systematic search was carried out from when registries began until February 2020. We also include a case diagnosed and treated in our department. Descriptive statistics were used to evaluate data, demographics, clinical findings, diagnostic modalities, therapeutics, and finally neurologic outcomes. The Kaplan-Meier method was used to assess overall survival and progression-free survival.

RESULTS

The final cohort comprises 35 patients. The mean age at diagnosis was 61.97 years, and 68.60% of the patients were male. SSA developed more frequently in the thoracic spine (48.60%), followed by the cervical spine (17.10%). Intradural lesions were rare, and the average neoplastic score for spinal instability was 9.5 points. The most common symptoms were impaired motor function (74.29%) and axial back pain (65.70%). After surgery, neurologic recovery was reported in 82.90% of cases. Mean progression-free survival and mean overall survival were 47.26 and 156.66 months.

CONCLUSIONS

SSA is a rare subgroup of localized amyloidosis, usually being diagnosed in male patients between the sixth and eighth decades. The gold standard treatment seems to be surgical resection. SSA patients have excellent long-term survival and a low rate of local recurrence.

MiR-144 overexpression as a promising therapeutic strategy to overcome glioblastoma cell invasiveness and resistance to chemotherapy

Glioblastoma (GB) is the most aggressive and common form of primary brain tumor, characterized by fast proliferation, high invasion, and resistance to current standard treatment. The average survival rate post-diagnosis is only of 14.6 months, despite the aggressive standard post-surgery treatment approaches of radiotherapy concomitant with chemotherapy with temozolomide. Altered cell metabolism has been identified as an emerging cancer hallmark, including in GB, thus offering a new target for cancer therapies. On the other hand, abnormal expression levels of miRNAs, key regulators of multiple molecular pathways, have been correlated with pathological manifestations of cancer, such as chemoresistance, proliferation, and resistance to apoptosis. In this work, we hypothesized that gene therapy based on modulation of a miRNA with aberrant expression in GB and predicted to target crucial metabolic enzymes might impair tumor cell metabolism. We found that the increase of miR-144 levels, shown to be downregulated in U87 and DBTRG human GB cell lines, as well as in GB tumor samples, promoted the downregulation of mRNA of enzymes involved in bioenergetic pathways, with consequent alterations in cell metabolism, impairment of migratory capacity, and sensitization of DBTRG cells to a chemotherapeutic drug, the dichloroacetate (DCA). Taken together, our findings provide evidence that the miR-144 plus DCA combined therapy holds promise to overcome GB-acquired chemoresistance, therefore deserving to be explored toward its potential application as a complementary therapeutic approach to the current treatment options for this type of brain tumor.

Laing early-onset distal myopathy with subsarcolemmal hyaline bodies caused by a novel variant in the MYH7 gene

Myopathies caused by MYH7 gene mutations are clinically and pathologically heterogeneous and, until recently, difficult to diagnose. The availability of NGS panels for hereditary neuromuscular diseases changed our insight regarding their frequency and allowed a better perception of the different phenotypes and morphological abnormalities associated.

We present a male Portuguese patient with the classical phenotype of Laing early-onset distal myopathy (MPD1) beginning at 6 years of age, very slowly progressive, and with a mild to moderate impact on daily life by the age of 56. Muscle biopsy showed a myopathic pattern with hyaline bodies and cores. The NGS panel for structural myopathies identified a novel missense heterozygous variant, c.T4652C (p.Leu1551Pro), in the exon 34 of the MYH7 gene.

Primary spinal epidural lymphoma: a rare entity with an ambiguous management

Lymphomas are malignant lymphoid tumours arising from lymphocytic cells. They usually develop in the lymphoid tissues and can spread to other organs; however, primary extra-nodal locations such as the spinal epidural space are less common. The authors report the case of a primary diffuse large B-cell lymphoma of the thoracic spine in a 65-year-old man, who presented to the emergency department with signs of upper motor neuron lesion. The patient underwent surgery in order to decompress the spinal cord. The treatment was concluded with six cycles of chemotherapy with methotrexate, rituximab, cyclophosphamide, vincristine and prednisone followed by radiotherapy. At the 24-month follow-up, no signs of epidural lesion or bone contrast enhancement were observed in thoracic spine MRI. Surgical decompression is recommended in patients with signs of spinal cord injury in order to prevent irreversible neurological damage and is related to high rates of disease-free survival.

Isomorphic diffuse glioma is a morphologically and molecularly distinct tumour entity with recurrent gene fusions of MYBL1 or MYB and a benign disease course

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.

Nucleolin is expressed in patient-derived samples and glioblastoma cells, enabling improved intracellular drug delivery and cytotoxicity

One of the major challenges in Glioblastoma (GBM) therapy relates with the existence of glioma stem-like cells (GSCs), known to be chemo- and radio-resistant. GSCs and non-stem GBM cells have the ability to interchange, emphasizing the importance of identifying common molecular targets among those cell sub-populations. Nucleolin overexpression has been recently associated with breast cancer sub-populations with different stem-like phenotype. The goal of this work was to evaluate the potential of cell surface nucleolin as a target in GBM cells. Different levels of nucleolin expression resulted in a 3.4-fold higher association of liposomes targeting nucleolin (functionalized with the nucleolin-binding F3 peptide) in U87, relative to GBM11 glioblastoma cells. Moreover, nucleolin was suggested as a potential marker in OCT4-, NANOG-positive GSC, and in the corresponding non-stem GBM cells, as well as in SOX2-positive GSC. Doxorubicin delivered by liposomes targeting nucleolin enabled a level of cytotoxicity that was 2.5- or 4.6-fold higher compared to the non-targeted counterparts. Importantly, an overexpression of nucleolin was also observed in cells of patient-derived samples, as compared with normal brain. Overall, these results suggested nucleolin as a therapeutic target in GBM.

Macrophagic myofasciitis: a challenging diagnosis

A 25-year-old man admitted for generalised muscle pain with an insidious onset 3 years ago. He had exercise intolerance and decrease in muscle strength, requiring gait support. He was previously healthy, with no chronic medication or recent history of drugs or toxics. National vaccination plan actualised with hepatitis B and tetanus vaccines administered 10 and 2 years, respectively, before symptom onset. No analytical, imaging or electromyography changes were found. Muscle biopsy revealed an inflammatory infiltrate predominantly macrophagic with aluminium deposits suggestive of macrophagic myofasciitis (MMF). It is probably associated with vaccines previously administered. MMF lesion can be regarded as pathological only if detected at least 18 months after last aluminic immunisation, as our case illustrates.

Prognostic stratification of adult primary glioblastoma multiforme patients based on their tumor gene amplification profiles

Several classification systems have been proposed to address genomic heterogeneity of glioblastoma multiforme, but they either showed limited prognostic value and/or are difficult to implement in routine diagnostics. Here we propose a prognostic stratification model for these primary tumors based on tumor gene amplification profiles, that might be easily implemented in routine diagnostics, and potentially improve the patients management. Gene amplification profiles were prospectively evaluated in 80 primary glioblastoma multiforme tumors using single-nucleotide polymorphism arrays and the results obtained validated in publicly available data from 267/347 cases. Gene amplification was detected in 45% of patients, and chromosome 7p11.2 including the EGFR gene, was the most frequently amplified chromosomal region – either alone (18%) or in combination with amplification of DNA sequences in other chromosomal regions (10% of cases). Other frequently amplified DNA sequences included regions in chromosomes 12q(10%), 4q12(7%) and 1q32.1(4%). Based on their gene amplification profiles, glioblastomas were subdivided into: i) tumors with no gene amplification (55%); ii) tumors with chromosome 7p/EGFR gene amplification (with or without amplification of other chromosomal regions) (38%); and iii) glioblastoma multiforme with a single (11%) or multiple (6%) amplified DNA sequences in chromosomal regions other than chromosome 7p. From the prognostic point of view, these amplification profiles showed a significant impact on overall survival of glioblastoma multiforme patients (p>0.001). Based on these gene amplification profiles, a risk-stratification scoring system was built for prognostic stratification of glioblastoma which might be easily implemented in routine diagnostics, and potentially contribute to improved patient management.

Novel mosaic mutation in the dystrophin gene causing distal asymmetric muscle weakness of the upper limbs and dilated cardiomyopathy

A group of heterogeneous muscle diseases are caused by dystrophin gene (DMD) mutations. We hereby present a male patient with a diagnosis of symptomatic dilated cardiomyopathy at 44 years-old who developed, soon after, weakness of distal right upper limb. At the age of 58, neurological examination revealed severe atrophy of right thenar muscles, flexion contractures on the right elbow, wrist and fingers, bilateral calf hypertrophy, myotatic areflexia in the upper limbs and hyporeflexia in the lower limbs. Manual muscle examination showed distal weakness of right upper limb muscles, severe on abductor pollicis brevis and extensor pollicis longus, and milder on interossei, finger extensors and brachioradialis muscles. Further testing revealed CK of 1500 U/L, a myopathic pattern on electromyography, and myopathic changes on right deltoid muscle biopsy, with immunohistochemistry showing focal sub-expression of dystrophin. Cardiac workup revealed a severe reduction in left ventricular ejection fraction, with a left ventricle of increased dimensions and global hypo-contractibility. A next-generation sequencing based panel for muscular diseases was performed and a nonsense mutation (c.C7525T) was identified in exon 51 of DMD gene, present in 70% of the gene readings (consistent with mosaicism).

Disclosing the functional changes of two genetic alterations in a patient with Chronic Progressive External Ophthalmoplegia: Report of the novel mtDNA m.7486G>A variant

Chronic Progressive External Ophthalmoplegia (CPEO) is characterized by ptosis and ophthalmoplegia and is usually caused by mitochondrial DNA (mtDNA) deletions or mt-tRNA mutations. The aim of the present work was to clarify the genetic defect in a patient presenting with CPEO and elucidate the underlying pathogenic mechanism. This 62-year-old female first developed ptosis of the right eye at the age of 12 and subsequently the left eye at 45 years, and was found to have external ophthalmoplegia at the age of 55 years. Histopathological abnormalities were detected in the patient's muscle, including ragged-red fibres, a mosaic pattern of COX-deficient muscle fibres and combined deficiency of respiratory chain complexes I and IV. Genetic investigation revealed the "common deletion" in the patient's muscle and fibroblasts. Moreover, a novel, heteroplasmic mt-tRNASer(UCN) variant (m.7486G>A) in the anticodon loop was detected in muscle homogenate (50%), fibroblasts (11%) and blood (4%). Single-fibre analysis showed segregation with COX-deficient fibres for both genetic alterations. Assembly defects of mtDNA-encoded complexes were demonstrated in fibroblasts. Functional analyses showed significant bioenergetic dysfunction, reduction in respiration rate and ATP production and mitochondrial depolarization. Multilamellar bodies were detected by electron microscopy, suggesting disturbance in autophagy. In conclusion, we report a CPEO patient with two possible genetic origins, both segregating with biochemical and histochemical defect. The "common mtDNA deletion" is the most likely cause, yet the potential pathogenic effect of a novel mt-tRNASer(UCN) variant cannot be fully excluded.

Intracranial myopericytoma: a tumour in a rare location

A 49-year-old female with history of headache, nausea and vomiting with some weeks of evolution, without neurological symptoms. Radiology revealed an expansive lesion near the inferior vermix and cerebellar tonsils, with heterogeneous gadolinium uptake and mass effect on the fourth ventricle, representing a probable extraventricular origin for the lesion. Pathological examination showed a proliferation of oval/spindle cell proliferation with eosinophil cytoplasm and small and monotonous nuclei, without mitoses. The cells had a concentric growth, surrounding thin-walled blood vessels with foci of stromal myxoid degeneration and whorled pattern. The vessels had a haemangiopericytoma pattern and were lined by non-atypical endothelial cells. The tumorous cells expressed vimentin, alpha-smooth actin and heavy-chain caldesmon and were negative for epithelial membrane antigen, protein S100, HMB45, CD34, calponin and desmin, thus providing the final diagnosis of intracranial myopericytoma.

The Expression of Connexins and SOX2 Reflects the Plasticity of Glioma Stem-Like Cells

Glioblastoma (GBM) is the most malignant primary brain tumor, with an average survival rate of 15 months. GBM is highly refractory to therapy, and such unresponsiveness is due, primarily, but not exclusively, to the glioma stem-like cells (GSCs). This subpopulation express stem-like cell markers and is responsible for the heterogeneity of GBM, generating multiple differentiated cell phenotypes. However, how GBMs maintain the balance between stem and non-stem populations is still poorly understood. We investigated the GBM ability to interconvert between stem and non-stem states through the evaluation of the expression of specific stem cell markers as well as cell communication proteins. We evaluated the molecular and phenotypic characteristics of GSCs derived from differentiated GBM cell lines by comparing their stem-like cell properties and expression of connexins. We showed that non-GSCs as well as GSCs can undergo successive cycles of gain and loss of stem properties, demonstrating a bidirectional cellular plasticity model that is accompanied by changes on connexins expression. Our findings indicate that the interconversion between non-GSCs and GSCs can be modulated by extracellular factors culminating on differential expression of stem-like cell markers and cell-cell communication proteins. Ultimately, we observed that stem markers are mostly expressed on GBMs rather than on low-grade astrocytomas, suggesting that the presence of GSCs is a feature of high-grade gliomas. Together, our data demonstrate the utmost importance of the understanding of stem cell plasticity properties in a way to a step closer to new strategic approaches to potentially eliminate GSCs and, hopefully, prevent tumor recurrence.

Phenotyping GABA transaminase deficiency: a case description and literature review

Gamma-aminobutyric acid transaminase (GABA-T) deficiency is an autosomal recessive disorder reported in only three unrelated families. It is caused by mutations in the ABAT gene, which encodes 4-aminobutyrate transaminase, an enzyme of GABA catabolism and mitochondrial nucleoside salvage. We report the case of a boy, deceased at 12 months of age, with early-onset epileptic encephalopathy, severe psychomotor retardation, hypotonia, lower-limb hyporeflexia, central hypoventilation, and rapid increase in weight and, to a lesser rate, length and head circumference. He presented signs of premature pubarche, thermal instability, and water-electrolyte imbalance. Serum total testosterone was elevated (43.3 ng/dl; normal range <16), as well as serum growth hormone (7.7 ng/ml; normal range <1). Brain magnetic resonance imaging (MRI) showed decreased myelination and generalized brain atrophy, later confirmed by post-mortem examination. ABAT gene sequencing was performed post-mortem, identifying a homozygous variant c.888G > T (p.Gln296His),not previously described. In vitro analysis concluded that this variant is pathogenic. The clinical features of this patient are similar to those reported so far in GABA-T deficiency. However, distinct mutations may have a different effect on enzymatic activity, which potentially could lead to a variable clinical outcome. Clinical investigation aiming for a diagnosis should not end with the patient's death, as it may allow a more precise genetic counselling for the family.

Characterization of an FTLD-PDB family with the coexistence of SQSTM1 mutation and hexanucleotide (G₄C₂) repeat expansion in C9orf72 gene

The C9orf72 expansion is considered a major genetic cause of familial frontotemporal dementia (FTD) in several patients' cohorts. Interestingly, C9orf72 expansion carriers, present also abundant neuronal p62-positive inclusions. Although p62/SQSTM1 mutations were initially associated with Paget disease of bone (PDB), they have been also identified in FTD. We describe an FTD-PDB family in which the proband presented with behavioral FTD phenotype and concomitant Paget disease. The molecular genetic analysis revealed the co-occurrence of 2 mutations; the pathogenic C9orf72 expansion and p.P392L heterozygous missense mutation in SQSTM1 gene. Amongst the 6 family members analyzed, the p.P392L SQSTM1 mutation segregated as expected with PDB, whereas the C9orf72 expansion segregated with frontal cognitive impairment or dementia in all but one carrier. The coexistence of these conditions could be underestimated since neither patients with FTD nor patients with PDB undergo bone scintigraphy or cognitive assessment, respectively. The number of cases with double mutations could also be over looked as the molecular strategy adopted in most laboratories ends with the identification of one pathogenic mutation in one of the known causative genes. Therefore, we advocate for further clinical and molecular evaluation in suspect cases.

Hiperintensidade Bilateral do Pulvinar e Núcleo Dorso-medial do Tálamo na Forma Esporádica da Doença de Creutzfeldt-Jakob

Introdução: A doença de Creutzfeldt-Jakob (DCJ) é uma patologia neurodegenerativa rapidamente progressiva causada por priões. O diagnóstico precoce e a determinação da sua forma revestem-se de importância epidemiológica, com forte impacto na saúde pública. A hiperintensidade bilateral do pulvinar, isoladamente (pulvinar sign) ou em associação com o núcleo dorso-medial dos tálamos (double hockey stick sign), no estudo de difusão, sequências ponderadas em T2 e fluid attenuated inversion recovery (FLAIR), é critério para o diagnóstico provável da forma variante da DCJ (vDCJ). A hiperdensidade bilateral dos caudados, putamina e córtex é o padrão habitualmente encontrado na forma esporádica da DCJ (eDCJ). Objectivo: Análise das alterações imagiológicas encontradas numa doente com eDCJ e hiperintensidade do pulvinar e núcleo dorsomedial dos tálamos, para avaliar a capacidade da RM diferenciar a vDCJ da eDCJ, na presença deste padrão lesional. Metodologia: Foi realizada uma ressonância magnética (RM) cerebral a uma doente do sexo feminino, 62 anos, com diagnóstico definitivo de eDCJ por estudo anatomopatológico do tecido cerebral. Análise qualitativa das imagens obtidas por RM, incluindo estudo de difusão e sequências ponderadas em T2 e FLAIR, bem como dos padrões lesionais encontrados. Resultados: A RM cerebral revelou hiperintensidade dos núcleos caudados, putamina, pulvinar e núcleo dorso-medial dos tálamos no estudo de difusão (com diminuição do coeficiente de difusão aparente), e sequências ponderadas em T2 e FLAIR, sendo que o hipersinal dos caudados e putamina revelou ser mais exuberante que a intensidade de sinal dos tálamos; hiperintensidade dos hipocampos e córtex frontal, temporal e parietal, mais exuberantes em FLAIR e no estudo de difusão. Comentário: A presença de hiperintensidade do pulvinar e núcleo dorso-medial dos tálamos na eDCJ poderá suscitar dúvidas no diagnóstico diferencial com a vDCJ. Só deverão ser considerados como verdadeiros pulvinar sign e double hockey stick sign, sugestivos de vDCJ, se a sua hiperintensidade for mais marcada que a intensidade de sinal dos caudados e putamina.

[Pituitary atypical adenoma or malignant corticotrophinoma?]

Pituitary tumors are classified into typical adenomas, atypical adenomas or carcinomas. Carcinoma represents 0.2% of pituitary tumors and is defined by the presence of metastases. It often presents as invasive and secreting macroadenoma, showing features of malignancy ab initio or over time. The high proliferative index (Ki-67) and immunostaining for p53 protein are common indicators of aggressiveness. We report a 58 years old male with invasive sellar incidentaloma. The hormonal study showed gonadal, thyroid, and somatotrophic failure, with increase of corticotropin (ACTH) and cortisol. Transsphenoidal surgery was performed and histology revealed a typical corticotrophinoma. The successive recurrences over 10 years led to five surgical reoperation and radiotherapy. After the third surgery, cellular atypia, Ki-67 of 27% and immunostaining for p53 were revealed. Subsequently, there were lesions suspicious of metastases (lung and lymph nodes), but the biopsy of the lymph nodes was inconclusive. The patient died before chemotherapy. In this case, the progressive loss of differentiation points to the need for early diagnosis, timely and aggressive treatment.

Detailed characterization of alterations of chromosomes 7, 9, and 10 in glioblastomas as assessed by single-nucleotide polymorphism arrays

Glioblastomas are cytogenetically heterogeneous tumors that frequently display alterations of chromosomes 7, 9p, and 10q. We used high-density (500K) single-nucleotide polymorphism arrays to investigate genome-wide copy number alterations and loss of heterozygosity in 35 primary glioblastomas. We focused on the identification and detailed characterization of alterations involving the most frequently altered chromosomes (chromosomes 7, 9, and 10), the identification of distinct prognostic subgroups of glioblastomas based on the cytogenetic patterns of alteration for these chromosomes, and validation of their prognostic impact in a larger series of tumors from public databases. Gains of chromosome 7 (97%), with or without epidermal growth factor receptor (EGFR) amplification, and losses of chromosomes 9p (83%) and 10 (91%) were the most frequent alterations. Such alterations defined five different cytogenetic groups with a significant effect on patient survival; notably, EGFR amplification (29%) was associated with a better survival among older patients, as confirmed by multivariate analysis of a larger series of glioblastomas from the literature. In addition, our results provide further evidence about the relevance of other genes (eg, EGFR, CDKN2A/B, MTAP) in the pathogenesis of glioblastomas. Altogether, our results confirm the cytogenetic heterogeneity of glioblastomas and suggest that their stratification based on combined assessment of cytogenetic alterations involving chromosomes 7, 9, and 10 may contribute to the prognostic evaluation of glioblastomas.

Limb-girdle muscular dystrophy in a Portuguese patient caused by a mutation in the telethonin gene

Limb-girdle muscular dystrophy 2G is caused by mutations in the telethonin (TCAP) gene in chromosome 17q11-12. This rare form of hereditary muscle disease was originally described in Brazilian patients and was recently identified in Chinese and Moldavian patients. We present the first Portuguese patient with a limb-girdle muscular dystrophy caused by a mutation in the TCAP gene. A Caucasian male, 50 years old, presented in his early twenties, slowly progressive weakness in upper and lower limbs. Neurologic examination revealed severe atrophy and weakness in the muscles of the arms, thighs and legs' anterior compartment. Muscle MRI of the thighs and legs revealed severe atrophy of all the muscles of the thighs and legs' anterolateral compartment, in a symmetrical way. Molecular studies identified the homozygous c.157C > T (p.Gln53X) mutation in exon 2 of the TCAP gene, already described in Brazilian patients.

Gene expression profiles of human glioblastomas are associated with both tumor cytogenetics and histopathology

Despite the increasing knowledge about the genetic alterations and molecular pathways involved in gliomas, few studies have investigated the association between the gene expression profiles (GEP) and both cytogenetics and histopathology of gliomas. Here, we analyzed the GEP (U133Plus2.0 chip) of 40 gliomas (35 astrocytic tumors, 3 oligodendrogliomas, and 2 mixed tumors) and their association with tumor cytogenetics and histopathology. Unsupervised and supervised analyses showed significantly different GEP in low- vs high-grade gliomas, the most discriminating genes including genes involved in the regulation of cell proliferation, apoptosis, DNA repair, and signal transduction. In turn, among glioblastoma multiforme (GBM), 3 subgroups of tumors were identified according to their GEP, which were closely associated with the cytogenetic profile of their ancestral tumor cell clones: (i) EGFR amplification, (ii) isolated trisomy 7, and (iii) more complex karyotypes. In summary, our results show a clear association between the GEP of gliomas and tumor histopathology; additionally, among grade IV astrocytoma, GEP are significantly associated with the cytogenetic profile of the ancestral tumor cell clone. Further studies in larger series of patients are necessary to confirm our observations.

Pediatric mitochondrial respiratory chain disorders in the Centro region of Portugal

The present study reviewed mitochondrial respiratory chain disorders diagnosed at the sole tertiary pediatric hospital in the Centro region of Portugal and estimated incidence and prevalence in this region. The Bernier criteria were used to retrospectively classify 200 children investigated from 1997 to 2006. A total of 78 patients were assigned with definite primary mitochondrial disorder, two thirds presenting in the first year of life. At presentation, 61 children had neuromuscular symptoms. Neurologic, ophthalmologic, growth retardation, muscular, cardiac, respiratory, hepatic, hematologic, and digestive symptoms were the most frequent clinical features. A classic mitochondrial syndrome was identified in 12 children, 6 of them with Leigh syndrome. Major respiratory chain enzymatic defects were detected in 73 cases. Pathogenic mitochondrial DNA or nuclear DNA mutations (or both) were observed in 9 children. Mortality was 29.5%, with median age of death at 8 months. Survival was shorter for patients with onset at infancy or children with liver or cardiac involvement, or with lactic acidosis. Estimated incidence of mitochondrial disorders in children less than 10-years-old was 1.5/10,000, and point prevalence was 5.4/100,000, respectively. These disorders seem to have a high incidence and poor prognosis in the Centro region of Portugal.

Novel progranulin mutation: screening for PGRN mutations in a Portuguese series of FTD/CBS cases

Mutations in the progranulin (PGRN) gene were recently described as the cause of ubiquitin positive frontotemporal dementia (FTD) in many families. Different frequencies of these genetic changes have been reported in diverse populations leading us to determine if these mutations were a major cause of FTD in the Portuguese population. The entire coding sequence plus exon 0 of PGRN were sequenced in a consecutive series of 46 FTD/CBS Portuguese patients. Two mutations were found: a novel pathogenic insertion (p.Gln300GlnfsX61) and a previously described point variant (p.T182M) of unclear pathogenicity. Pathogenic mutations in the PGRN gene were found in one of the 36 probands studied (3% of the probands in our series) who had a corticobasal syndrome presentation, indicating that in the Portuguese population, mutations in this gene are not a major cause of FTD.

Patient gender is associated with distinct patterns of chromosomal abnormalities and sex chromosome linked gene-expression profiles in meningiomas

The female predominance of meningiomas has been established, but how this is affected by hormones is still under discussion. We analyzed the characteristics of meningiomas from male (n = 53) and female (n = 111) patients by interphase fluorescence in situ hybridization (iFISH). In addition, in a subgroup of 45 (12 male and 33 female) patients, tumors were hybridized with the Affymetrix U133A chip. We show a higher frequency of larger tumors (p = .01) and intracranial meningiomas (p = .04) together with a higher relapse rate (p = .03) in male than in female patients. Male patients had a higher percentage of del(1p36) (p < .001), while loss of an X chromosome was restricted to tumors from female patients (p = .008). In turn, iFISH studies showed a higher frequency of chromosome losses, other than monosomy 22 alone, in meningiomas from male patients (p = .002), while female patients displayed a higher frequency of chromosome gains (p = .04) or monosomy 22 alone (p = .03) in the ancestral tumor clone. Interestingly, individual chromosomal abnormalities had a distinct impact on the recurrence-free survival rate of male versus female patients. In turn, gene expression showed that eight genes (RPS4Y1, DDX3Y, JARID1D, DDX3X, EIF1AY, XIST, USP9Y, and CYorf15B) had significantly different expression patterns (R(2) > 0.80; p < .05) in tumors from male and female patients. In summary, we show the existence of different patterns of chromosome abnormalities and gene-expression profiles associated with patient gender, which could help to explain the slightly different clinical behavior of these two patient groups.

Null mutations and lethal congenital form of glycogen storage disease type IV

Glycogen branching enzyme deficiency (glycogen storage disease type IV, GSD-IV) is a rare autosomal recessive disorder of the glycogen synthesis with high mortality. Two female newborns showed severe hypotonia at birth and both died of cardiorespiratory failure, at 4 and 12 weeks, respectively. In both patients, muscle biopsies showed deposits of PAS-positive diastase-resistant material and biochemical analysis in cultured fibroblasts showed markedly reduced glycogen branching enzyme activity. Direct sequencing of GBE1 gene revealed that patient 1 was homozygous for a novel c.691+5 g>c in intron 5 (IVS5+5 g>c). RT-PCR analysis of GBE1 transcripts from fibroblasts cDNA showed that this mutation produce aberrant splicing. Patient 2 was homozygous for a novel c.1643G>A mutation leading to a stop at codon 548 in exon 13 (p.W548X). These data underscore that in GSD-IV a severe phenotype correlates with null mutations, and indicate that RNA analysis is necessary to characterize functional consequences of intronic mutations.

[ACTH-dependent Cushing's syndrome: a revision of 43 cases]

AIM

To evaluate the characteristics and outcomes of the patients diagnosed as ACTH-dependent Cushing syndrome, registered in the department.

MATERIAL AND METHODS

We reviewed the files of forty-three patients followed from 1974 to 2002.

RESULTS

A progressive rise in the number of patients diagnosed was found, being 80% females. Clinical suspicion was based mostly on the typical fat distribution; hirsutism and amenorrhoea were important in women. The more reliable diagnostic tests were: 11 pm cortisol, day curve of ACTH and cortisol, and dexamethasone suppression tests. The ACTH response to CRH during inferior petrosal sinus sampling permitted the diagnosis of ectopic source. In thirty-seven patients a pituitary adenoma was diagnosed. The three patients diagnosed before 1985 went for bilateral adrenalectomy (Nelson's syndrome in two); the others were submitted to transsphenoidal pituitary adenomectomy, obtaining remission in twenty six at the first operation and in two others at the second. Three patients had a recidive. Of the six patients with persistent disease (all treated with metyrapone or ketoconazole), three were submitted to radiotherapy, two to bilateral adrenalectomy, and one was waiting for surgery. Four patients had a bronchial carcinoid, successfully removed in three. One patient was lost to follow-up and another was still being evaluated.

CONCLUSIONS

We found a positive evolution in the capacity to diagnose and treat these patients. Neurosurgical ability to achieve remission was 80% in the operated cases. More effective technical methods and drugs, as well as a multidisciplinary and dedicated medical team, lead to long lasting remissions in most of the patients.

Cystic intraventricular schwannoma: case report and review of the literature

Intraventricular schwannoma is an exceedingly rare tumour with only 6 cases described in the literature. One case of a cystic intraventricular schwannoma operated on at our Institution is analyzed and the other cases reported in the literature are reviewed. Complete removal was achieved and no recurrence was noted after a follow-up period of 10 years. Intraventricular schwannomas are rare tumours that are amenable to complete surgical removal, having a good prognosis without the need of adjuvant therapy.