David Scheie’s research while affiliated with IT University of Copenhagen and other places

Aggressive pituitary neuroendocrine tumors (PitNETs)/adenomas are characterized by progressive growth despite surgery and all standard medical therapies and radiotherapy. A subset will metastasize to the brain and/or distant locations and are termed metastatic PitNETs (pituitary carcinomas). Studies of potential prognostic markers have been limited due to the rarity of these tumors. A few recurrent somatic mutations have been identified, and epigenetic alterations and chromosomal rearrangements have not been explored in larger cohorts of aggressive and metastatic PitNETs. In this study, we performed genome-wide methylation analysis, including copy-number variation (CNV) calculations, on tumor tissue specimens from a large international cohort of 64 patients with aggressive (48) and metastatic (16) pituitary tumors. Twelve patients with non-invasive pituitary tumors (Knosp 0–2) exhibiting an indolent course over a 5 year follow-up served as controls. In an unsupervised hierarchical cluster analysis, aggressive/metastatic PitNETs clustered separately from benign pituitary tumors, and, when only specimens from the first surgery were analyzed, three separate clusters were identified: aggressive, metastatic, and benign PitNETs. Numerous CNV events affecting chromosomal arms and whole chromosomes were frequent in aggressive and metastatic, whereas benign tumors had normal chromosomal copy numbers with only few alterations. Genome-wide methylation analysis revealed different CNV profiles and a clear separation between aggressive/metastatic and benign pituitary tumors, potentially providing biomarkers for identification of these tumors with a worse prognosis at the time of first surgery. The data may refine follow-up routines and contribute to the timely introduction of adjuvant therapy in patients harboring, or at risk of developing, aggressive or metastatic pituitary tumors.

Glioblastoma remains one of the deadliest brain malignancies. First-line therapy consists of maximal surgical tumor resection, chemotherapy, and radiotherapy. Malignant cells escape surgical resection by migrating into the surrounding healthy brain tissue, where they give rise to the recurrent tumor. Gene expression profiling allows glioblastoma tumor cores to be classified into mesenchymal, proneural, and classical subtypes, each with distinct genetic alterations and cellular compositions. In contrast, the adjacent brain parenchyma where infiltrating malignant cells escape surgical resection is less characterized in patients. Using single-cell and multicellular resolution spatial transcriptomics on tissues from both the tumor core and infiltrated brain tissue (n = 11), we compared the transcriptional profiles of malignant cells in these regions. Malignant cells near regions with microvascular proliferation showed increased expression of genes related to vascular homeostasis. Within tumor cores, proneural and mesenchymal subtypes exhibited distinct spatial gene expression patterns, although these differences were reduced in the infiltrated brain tissue, apart from gene expression due to chromosomal alterations specific to the proneural subtype. We identified two transcriptional patterns of brain infiltration, with the dominant pattern showing a transition from mesenchymal to proneural states. This transition was accompanied by increased expression of genes linked to neurodevelopmental pathways and glial cell differentiation. Additionally, one gene module upregulated in infiltrating malignant cells was predictive of poor patient survival and enriched for genes associated with differentiated neuronal cells. Together, our findings provide an updated view of the spatial landscape of glioblastomas and infiltrated brain tissue, furthering our understanding of the malignant cells that invade healthy brain. This insight offers new avenues for targeted therapy after surgical resection of the primary tumor.

BACKGROUND The extent of meningioma resection is the most fundamental risk factor for recurrence and exact knowledge of extent of resection is necessary for prognostication and for planning of adjuvant treatment. Currently used classifications are the EANO-grading and the Simpson grading. The former comprises radiological imaging with contrast-enhanced MRI and differentiation between “gross total removal” and “subtotal removal”, while the latter comprises a five-tiered differentiation of the surgeon’s impression of the extent of resection. The extent of resection of tumors is usually defined via analyses of resection margins but has until now not been implemented for meningiomas. PET/MRI imaging with 68Ga-DOTATOC allows more sensitive and specific imaging than MRI following surgery of meningiomas. OBJECTIVE To develop an objective grading system based on microscopic analyses of resection margins and sensitive radiological analyses to improve management of follow-up, adjuvant therapy and prognostication of meningiomas. Based on the rationale of resection-margin analyses as gold standard and superior imaging performance of 68Ga DOTATOC PET, we propose “Copenhagen Grading” for meningiomas. PRELIMINARY RESULTS Since April 2021, Copenhagen Grading has been implemented prospectively as a clinical standard at Rigshospitalet, Copenhagen, with 264 patients enrolled thus far. DOTATOC PET was used for follow-up in 212 subjects, while resection margin biopsies were obtained from 90 subjects. DOTATOC-PET revealed residual tumor in 33% (55/168) of cases where MRI results were inconclusive and in 28% (47/168) of cases where MRI showed no residual tumor. CONCLUSION Copenhagen Grading offers a comprehensive, logical, and reproducible means of defining resection extent, showing potential as the most sensitive and specific grading. Further long term evaluation of the clinical implication of biopsies and the cost-effectiveness of DOTATOC PET is necessary during the prospective implementation.

BACKGROUND Proton radiation therapy (PRT) has since 2019 become a treatment option alongside photon therapy in Denmark. PRT reduces doses to normal brain structures and for gliomas PRT has been considered in oligodendroglioma WHO grade 2-3 (O2-3) and astrocytoma IDH mutated WHO grade 2-4 (A2-4). Concerns have been raised regarding the frequency of treatment-related effects. The aim of this study is to investigate the association between pathology results and metabolic activity when progression is suspected on MRI after PRT in glioma. MATERIAL AND METHODS Forty-nine patients from Rigshospitalet, Copenhagen, Denmark suffering from glioma were treated with PRT until October 2022 (mean age 41 years, range 23-65), and followed for a minimum 1.5 years until April 2024. Progression was suspected in 20 patients clinically and/or at MRI, of which 13 patients fulfilled the criteria of the study: a [18F]FET PET scan followed by first subsequent pathology assessment after PRT (biopsy n=8 and resection n=5, mean delay after PET imaging 18 days (range 1-50 days), mean interval after PRT 1.6 years (range 0.3-3.3 years). The initial pathology of gliomas were O3 n=5, A2 n=1, A3 n=5, A4 n=2. PET scans were performed 20 min after injection of approximately 200 MBq [18F]FET. The maximal metabolic activity relatively to healthy appearing cortex (TBRmax) was calculated for the suspicious lesion. RESULTS Tumor relapse was found in four patients (subsequent pathology A3 n=1, A4 n=3) with corresponding TBRmax of mean 3.1 (range 2.3-4.3). Pathology showed only treatment related effects in eight patients (initial pathology O3 n=5, A3 n=2 A4 n=1), with corresponding TBRmax of mean 1.8 (range 1.6-2.3), though one of these patients died 2.3 years later from tumor relapse. Mixed reactive changes and A2 tumor were found in the resected tissue of one patient with corresponding TBRmax of 1.6. Thus, the metabolic activity was significantly higher in tumor tissue compared to treatment-related effects using Students t-test, p=0.02 when classifying mixed as relapse (p= 0.002 when excluding mixed), and ROC AUC was 0.80 providing sens/spec of 80%/88% at an optimal TBRmax cut-off at 2.2. CONCLUSION The prevalence of treatment-related effects verified by histopathology was 16% in the patients treated with PRT during at least 1.5 year follow-up. A significantly lower metabolic activity was found in the treatment-related effects compared to tumor relapse measured with [18F]FET PET imaging. Indicating that [18F]FET PET imaging may be a valuable diagnostic tool to discriminate between relapse and treatment-related effects at an early stage after PRT. However, in our experience, reactive changes often expand over time and the metabolic intensity might accordingly increase later in the progress after PRT. For investigating this, systematic repeated [18F]FET PET imaging is needed.

Aims DNA methylation profiling, recently endorsed by the World Health Organisation (WHO) as a pivotal diagnostic tool for brain tumours, most commonly relies on bead arrays. Despite its widespread use, limited data exist on the technical reproducibility and potential cross‐institutional differences. The LOGGIC Core BioClinical Data Bank registry conducted a prospective laboratory comparison trial with 12 international laboratories to enhance diagnostic accuracy for paediatric low‐grade gliomas, focusing on technical aspects of DNA methylation data generation and profile interpretation under clinical real‐time conditions. Methods Four representative low‐grade gliomas of distinct histologies were centrally selected, and DNA extraction was performed. Participating laboratories received a DNA aliquot and performed the DNA methylation‐based classification and result interpretation without knowledge of tumour histology. Additionally, participants were required to interpret the copy number profile derived from DNA methylation data and conduct DNA sequencing of the BRAF hotspot p.V600 due to its relevance for low‐grade gliomas. Results had to be returned within 30 days. Results High technical reproducibility was observed, with a median pairwise correlation of 0.99 (range 0.94–0.99) between coordinating laboratory and participants. DNA methylation‐based tumour classification and copy number profile interpretation were consistent across all centres, and BRAF mutation status was accurately reported for all cases. Eleven out of 12 centres successfully reported their analysis within the 30‐day timeframe. Conclusion Our study demonstrates remarkable concordance in DNA methylation profiling and profile interpretation across 12 international centres. These findings underscore the potential contribution of DNA methylation analysis to the harmonisation of brain tumour diagnostics.

Glioblastoma remains one of the deadliest brain malignancies. First-line therapy consists of maximal surgical tumor resection, accompanied by chemotherapy and radiotherapy. Malignant cells escape surgical resection by migrating into the surrounding healthy brain tissue, where they give rise to the recurrent tumor. Based on gene expression, tumor cores can be subtyped into mesenchymal, proneural, and classical tumors, each being associated with differences in genetic alterations and cellular composition. In contrast, the adjacent brain parenchyma where infiltrating malignant cells escape surgical resection is less characterized in patients. Using spatial transcriptomics (n = 11), we show that malignant cells within proneural or mesenchymal tumor cores display spatially organized differences in gene expression, although such differences decrease within the infiltrated brain tissue. Malignant cells residing in infiltrated brain tissue have increased expression of genes related to neurodevelopmental pathways and glial cell differentiation. Our findings provide an updated view of the spatial landscape of glioblastomas and further our understanding of the malignant cells that infiltrate the healthy brain, providing new avenues for the targeted therapy of these cells after surgical resection.

Purpose This 13-year consecutive case series aims to provide a comprehensive overview of all patients operated for clival chordomas and clival chondrosarcomas in Denmark since the centralization of treatment in 2010, comparing outcomes to international series. Methods This was a retrospective review of 33 patients with clival tumors, comprising 22 chordomas and 11 chondrosarcomas, who were treated at Copenhagen University Hospital between years 2010 and 2023. Data were collected from digital patient records and pathology reports. Results The symptoms leading to diagnosis primarily included double vision, headaches, and dizziness. In general, patients were in good health, with a mean Charlson Comorbidity Index score of 1.6. The complication rate of the index surgery was 51.5%. Adjuvant radiotherapy was applied in 51.5% of the cases. In patients with clival chordomas, the mean age was 51.1 years, ranging from 16 to 83 years. At the time of diagnosis, the mean tumor volume was 20.9 cm³ and the five-year overall survival rates were 79.1% (95% confidence interval (CI): 62.4–100). In patients with chondrosarcomas, the mean age was 48.2 years, ranging from 15 to 76 years. At the time of diagnosis, the mean tumor volume was 22.3 cm³ and the five-year overall survival 90% (95% CI: 73.2–100). Conclusion The centralized treatment of clival tumors in Denmark demonstrates incidence, survival, and complication rates comparable to those found in other international series. Given the variations in treatment strategies, tumor localizations across series, and small sample sizes, the further analysis of larger compiled multicenter datasets for clival tumors could provide more solid evidence regarding the management of these rare tumors.

Intracranial mesenchymal tumor, FET-CREB fusion positive, is a newly recognized and rare CNS tumor that occurs primarily in children and young adults. It is regarded as the intracranial variant of angiomatoid fibrous histiocytoma. Extracranial angiomatoid fibrous histiocytomas are typically located in the extremities and usually discernible on a ¹⁸ F-FDG PET/CT scanning. We present a 50-year-old man with recurrence of a primary intracranial mesenchymal tumor with equivocal ¹⁸ F-FDG PET/CT findings but with subsequent highly increased metabolic activity using ¹⁸ F-FET PET/CT confirming tumor recurrence. This case highlights the importance of ¹⁸ F-FET PET/CT, as opposed to ¹⁸ F-FDG, in the clinical evaluation of this rare intracranial mesenchymal tumor.

Glioblastoma remains one of the deadliest brain malignancies. First-line therapy consists of maximal surgical tumor resection, accompanied by concomitant and adjuvant temozolomide chemotherapy and radiotherapy. Malignant cells escape surgical resection by migrating into the brain parenchyma, where they give rise to the recurrent tumor. Based on gene expression, the tumor core can be subtyped into mesenchymal, proneural and classical areas, each being associated with differences in genetic alterations and cellular composition. In contrast, the tumor periphery where migrating tumor cells infiltrate brain parenchyma is less characterized in patients. Using spatial transcriptomics (n = 11), we show that specific malignant states colocalize in tumor core areas with necrosis and microvascular proliferation. Malignant cells within proneural or mesenchymal subtyped cores displayed, as expected, many differences in genetic expression, although such differences disappeared in the tumor periphery. Malignant cells residing in the tumor periphery had increased expression of genes related to neurodevelopmental pathways and synaptic connectivity. Our findings show similarities in cellular states across tumor subtypes with implications for post-operative treatment and provide an updated view of the spatial landscape of glioblastomas. Citation Format: Dylan Harwood, Vilde Pedersen, Nicolai S. Bager, Ane Y. Schmidt, Tobias O. Stannius, Ausrine Areskeviciute, Knud Josefsen, Dorte S. Nørøxe, David Scheie, Hannah E. Rostalski, Ulrik Lassen, Frederik O. Bagger, Joachim Weischenfeldt, Dieter H. Heiland, Kristoffer Vitting-Seerup, Signe R. Michaelsen, Bjarne W. Kristensen. Glioblastoma cells increase expression of neurodevelopmental programs and synaptic connectivity in the tumor periphery [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1144.