Glioblastoma is characterized by widespread genetic and transcriptional heterogeneity, yet little is known about the role of the epigenome in glioblastoma disease progression. Here, we present ...genome-scale maps of DNA methylation in matched primary and recurring glioblastoma tumors, using data from a highly annotated clinical cohort that was selected through a national patient registry. We demonstrate the feasibility of DNA methylation mapping in a large set of routinely collected FFPE samples, and we validate bisulfite sequencing as a multipurpose assay that allowed us to infer a range of different genetic, epigenetic, and transcriptional characteristics of the profiled tumor samples. On the basis of these data, we identified subtle differences between primary and recurring tumors, links between DNA methylation and the tumor microenvironment, and an association of epigenetic tumor heterogeneity with patient survival. In summary, this study establishes an open resource for dissecting DNA methylation heterogeneity in a genetically diverse and heterogeneous cancer, and it demonstrates the feasibility of integrating epigenomics, radiology, and digital pathology for a national cohort, thereby leveraging existing samples and data collected as part of routine clinical practice.
Background
Bone infiltration of the tumour is common in meningioma surgery. This may also affect patients without indicative signs of bone infiltration on preoperative imaging. Unrecognized bone ...invasion may lead to higher recurrence rates. 5-ALA fluorescence–guided resection (5-ALA-fg) could be a promising tool to help recognize possible bone invasion and/or tumour remnants. However, there is still little data about 5-ALA-fg resection in bone and soft tissue infiltrating meningiomas.
Methods
We performed a retrospective study of 11 patients who were operated with the aid of 5-ALA due to bone and soft tissue infiltrating meningiomas at the University Hospital of St. Poelten between 2013 and 2019.
Results
Strong and homogeneous fluorescence of the meningioma was observed in 9 cases (81.8%) and vague and heterogeneous fluorescence in 2 cases (18.2%). Hyperostosis on computerized tomography was evident in 3 of 6 cases (50%) and bone infiltration was visible in preoperative magnetic resonance imaging in 7 of 11 patients (63.6%). All eleven patients showed positive fluorescence of the bone infiltrating part. In all 7 cases where tissue could be collected, histopathological testing verified tumour infiltration (100%). There was also fluorescence of the periosteum in 3 cases and histopathological testing verified tumour infiltration in 100%.
Conclusion
There is growing evidence that 5-ALA-fg resection can help to identify bone infiltration in meningioma surgery. Therefore, it may help to improve extent of resection. However, further studies are necessary to investigate the rate of false-negative fluorescence and its effect on progression free survival. If 5-ALA-fg resection of meningioma is performed, the attending surgeon should also consider investigating the adjacent periosteum under blue light for detection of possible fluorescence.
Background Corticosteroid therapy (CST) prior to biopsy may hinder histopathological diagnosis in primary central nervous system lymphoma (PCNSL). Therefore, preoperative CST in patients with ...suspected PCNSL should be avoided if clinically possible. The aim of this study was thus to analyze the difference in the rate of diagnostic surgeries in PCNSL patients with and without preoperative CST. Methods A multicenter retrospective study including all immunocompetent patients diagnosed with PCNSL between 1/2004 and 9/2018 at four neurosurgical centers in Austria was conducted and the results were compared to literature. Results A total of 143 patients were included in this study. All patients showed visible contrast enhancement on preoperative MRI. There was no statistically significant difference in the rate of diagnostic surgeries with and without preoperative CST with 97.1% (68/70) and 97.3% (71/73), respectively (p = 1.0). Tapering and pause of CST did not influence the diagnostic rate. Including our study, there are 788 PCNSL patients described in literature with an odds ratio for inconclusive surgeries after CST of 3.3 (CI 1.7-6.4). Conclusions Preoperative CST should be avoided as it seems to diminish the diagnostic rate of biopsy in PCNSL patients. Yet, if CST has been administered preoperatively and there is still a contrast enhancing lesion to target for biopsy, surgeons should try to keep the diagnostic delay to a minimum as the likelihood for acquiring diagnostic tissue seems sufficiently high. Keywords: Primary central nervous system lymphoma, Corticosteroid therapy, Diagnostic rate
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Sex-specific differences have been increasingly recognized in many human diseases including brain cancer, namely glioblastoma. Primary CNS lymphoma (PCNSL) is an exceedingly rare type of brain cancer ...that tends to have a higher incidence and worse outcomes in male patients. Yet, relatively little is known about the reasons that contribute to these observed sex-specific differences. Using a population-representative cohort of patients with PCNSL with dense magnetic resonance (MR) imaging and digital pathology annotation (n = 74), we performed sex-specific cluster and survival analyses to explore possible associations. We found three prognostically relevant clusters for females and two for males, characterized by differences in (i) patient demographics, (ii) tumor-associated immune response, and (iii) MR imaging phenotypes. Upon a multivariable analysis, an enhanced FoxP3+ lymphocyte-driven immune response was associated with a shorter overall survival particularly in female patients (HR 1.65, p = 0.035), while an increased extent of contrast enhancement emerged as an adverse predictor of outcomes in male patients (HR 1.05, p < 0.01). In conclusion, we found divergent prognostic constellations between female and male patients with PCNSL that suggest differential roles of tumor-associated immune response and MR imaging phenotypes. Our results further underline the importance of continued sex-specific analyses in the field of brain cancer.
Summary Background and objectives Basal and squamous cell carcinoma (BCC, SCC), collectively referred to as keratinocyte‐derived skin cancer (KC), are the most common human cancers worldwide. Surgery ...is the treatment of choice, but may represent overtreatment in the very elderly. This study aims to address this issue by investigating the life expectancy of patients over 80 years after surgery. Patients and methods A single‐center, retrospective study was performed to include surgically treated KC patients at the Department of Dermatology and Venereology of the University Hospital in St. Pölten, Austria, between 01.01.2011 and 31.12.2017, who were 80 years or older. Data on individual survival (cut‐off April 30, 2020), date and cause of death were retrieved from the Austrian national demographic database at Statistics Austria (Vienna). Results 940 patients (450 female, 490 male, 639 BCCs, 301 SCCs) were included with 307 being alive at the cut‐off date. Median postoperative survival was 57 months (95% CI, 54–63 months). Conclusions With a median postoperative survival of almost 5 years, surgery remains a valid treatment option for KC at the end of life. However, 77 of the treated patients died within a year after surgery and preoperative assessment might have helped to avoid overtreatment in some of these cases.
Recently, a family with idiopathic brain calcification was reported, in which one family member was diagnosed with multiple system atrophy (MSA) at autopsy. We report here a case showing similar ...neuropathological features in a patient with longstanding hypoparathyroidism. Our female patient had a history of hypoparathyroidism with hypocalcaemia and tetany since the age of 9 years. In her 50s she developed dementia and parkinsonism. She died of myocardial infarction aged 65 years. Neuropathology showed severe brain calcifications of the Fahr type in the basal ganglia, thalami, cerebral and cerebellar white matter and dentate nuclei. Additionally, there was prominent alpha‐synucleinopathy of the multiple system atrophy type (MSA). The patient has a healthy identical twin and there is no family history of hypoparathyroidism or neurological disease. Data on alpha‐synuclein accumulation in various cases of Fahr's syndrome are needed to establish the correlation between alpha‐synucleinopathy and bilateral striopallidodentate calcification.
Chondroitin sulfate proteoglycan 4 (CSPG4) is a multifunctional transmembrane proteoglycan involved in spreading, migration and invasion of melanoma. In addition to the activating BRAF V600E ...mutation, CSPG4 was shown to promote MAPK signaling by mediating the growth‑factor induced activation of receptor tyrosine kinases. However, it remains elusive which factors regulate CSPG4 expression. Therefore, the aim of the present study was to examine whether BRAF and MEK inhibitors have an effect on the expression of CSPG4. We exposed a panel of BRAF‑mutant CSPG4‑positive or ‑negative melanoma cell lines to BRAF and MEK inhibitors. Protein levels of CSPG4 were analyzed by flow cytometry (FACS), immunofluorescence microscopy (IF), and western blotting.
mRNA levels were determined by quantitative PCR (qPCR). The prolonged exposure of cells to BRAF and MEK inhibitors resulted in markedly reduced levels of the CSPG4 protein in permanent resistant melanoma cells as well as decreased levels of its mRNA. We did not observe increasing levels of CSPG4 shedding into the culture supernatants. In addition, patient‑derived matched tumor samples following therapy with kinase inhibitors showed decreased numbers of CSPG4‑positive cells as compared to pre‑therapy tumor samples. Our results indicate that BRAF and MEK inhibition downregulates CSPG4 expression until the cells have developed permanent resistance. Our findings provide the basis for further investigation of the role of CSPG4 in the development of drug‑resistance in melanoma cells.
Purpose To explore the diagnostic performance of physiological magnetic resonance (MR) imaging of oxygen metabolism and neovascularization activity for grading and characterization of isocitrate ...dehydrogenase (IDH) gene mutation status of gliomas. Materials and Methods This retrospective study had institutional review board approval; written informed consent was obtained from all patients. Eighty-three patients with histopathologically proven glioma (World Health Organization WHO grade II-IV) were examined with quantitative blood oxygen level-dependent imaging and vascular architecture mapping. Biomarker maps of neovascularization activity (microvessel radius, microvessel density, and microvessel type indicator MTI) and oxygen metabolism (oxygen extraction fraction OEF and cerebral metabolic rate of oxygen CMRO
) were calculated. Receiver operating characteristic analysis was used to determine diagnostic performance for grading and detection of IDH gene mutation status. Results Low-grade (WHO grade II) glioma showed areas with increased OEF (+18%, P < .001, n = 20), whereas anaplastic glioma (WHO grade III) and glioblastoma (WHO grade IV) showed decreased OEF when compared with normal brain tissue (-54% P < .001, n = 21 and -49% P < .001, n = 41, respectively). This allowed clear differentiation between low- and high-grade glioma (area under the receiver operating characteristic curve AUC, 1) for the patient cohort. MTI had the highest diagnostic performance (AUC, 0.782) for differentiation between gliomas of grades III and IV among all biomarkers. CMRO
was decreased (P = .037) in low-grade glioma with a mutated IDH gene, and MTI was significantly increased in glioma grade III with IDH mutation (P = .013) when compared with the IDH wild-type counterparts. CMRO
showed the highest diagnostic performance for IDH gene mutation detection in low-grade glioma (AUC, 0.818) and MTI in high-grade glioma (AUC, 0.854) and for all WHO grades (AUC, 0.899) among all biomarkers. Conclusion MR imaging-derived oxygen metabolism and neovascularization characterization may be useful for grading and IDH mutation detection of gliomas and requires only 7 minutes of extra imaging time.
RSNA, 2016 Online supplemental material is available for this article.
Insufficient control of infiltrative glioblastoma (GBM) cells is a major cause of treatment failure and tumor recurrence. Hence, detailed insights into pathophysiologic changes that precede GBM ...recurrence are needed to develop more precise neuroimaging modalities for tailored diagnostic monitoring and therapeutic approaches.
Overall, 168 physiologic MRI follow-up examinations of 56 patients with GBM who developed recurrence after standard therapy were retrospectively evaluated, that is, two post-standard-therapeutic follow-ups before and one at radiological recurrence. MRI biomarkers for microvascular architecture and perfusion, neovascularization activity, oxygen metabolism, and hypoxia were determined for brain areas that developed in the further course into recurrence and for the recurrent GBM itself. The temporal pattern of biomarker changes was fitted with locally estimated scatterplot smoothing functions and analyzed for pathophysiologic changes preceding radiological GBM recurrence.
Our MRI approach demonstrated early pathophysiologic changes prior to radiological GBM recurrence in all patients. Analysis of the time courses revealed a model for the pathophysiology of GBM recurrence: 190 days prior to radiological recurrence, vascular cooption by GBM cells induced vessel regression, detected as decreasing vessel density/perfusion and increasing hypoxia. Seventy days later, neovascularization activity was upregulated, which reincreased vessel density and perfusion. Hypoxia, however, continued to intensify for 30 days and peaked 90 days before radiological recurrence.
Hypoxia may represent an early sign for GBM recurrence. This might become useful in the development of new combined diagnostic-therapeutic approaches for tailored clinical management of recurrent GBM. Further preclinical and in-human studies are required for validation and evaluation.
The intratumoral heterogeneity of oxygen metabolism in combination with variable patterns of neovascularization (NV) as well as reprogramming of energy metabolism affects the landscape of tumor ...microenvironments (TMEs) in glioblastoma. Knowledge of the hypoxic and perivascular niches within the TME is essential for understanding treatment failure.
Fifty-two patients with untreated glioblastoma (isocitrate dehydrogenase 1 wild type IDH1wt) were examined with a physiological MRI protocol including a multiparametric quantitative blood oxygen level dependent (qBOLD) approach and vascular architecture mapping (VAM). Imaging biomarker information about oxygen metabolism (mitochondrial oxygen tension) and neovascularization (microvascular density and type) were fused for classification of 6 different TMEs: necrosis, hypoxia with/without neovascularization, oxidative phosphorylation (OxPhos), and glycolysis with/without neovascularization. Association of the different TME volume fractions with progression-free survival (PFS) was assessed using Kaplan-Meier analysis and Cox proportional hazards models.
A common spatial structure of TMEs was detected: central necrosis surrounded by tumor hypoxia (with defective and functional neovasculature) and different TMEs with a predominance of OxPhos and glycolysis for energy production, respectively. The percentage of the different TMEs on the total tumor volume uncovered 2 clearly different subtypes of glioblastoma IDH1wt: a glycolytic dominated phenotype with predominantly functional neovasculature and a necrotic/hypoxic dominated phenotype with approximately 50% of defective neovasculature. Patients with a necrotic/hypoxic dominated phenotype showed significantly shorter PFS (P = 0.035).
Our non-invasive mapping approach allows for classification of the TME and detection of tumor-supportive niches in glioblastoma which may be helpful for both clinical patient management and research.
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