18F-FET PET/CT in Advanced Head and Neck Squamous Cell Carcinoma: an Intra-individual Comparison with 18F-FDG PET/CT

Purpose: To assess the diagnostic value of O-2-fluoro-18(F)-ethyl-l-tyrosine (18F-FET) positron emission tomography/computed tomography (PET/CT) for patients with advanced head and neck squamous cell carcinoma compared with 18F-fluoro-2-deoxy-d-glucose (18F-FDG) PET/CT at initial staging and following radiochemotherapy. Procedures: Thirteen patients were prospectively enrolled; each of them underwent an 18F-FDG PET/CT and 18F-FET PET/CT before treatment. Ten of those were scanned 10weeks after treatment. Results: Sensitivity, specificity, and accuracy for 18F-FDG PET/CT (primary and lymph node metastases) at initial staging were 89%, 50%, and 81%. For 18F-FET PET/CT the numbers were 70%, 90%, and 74%. Sensitivity, specificity, and accuracy for 18F-FDG PET/CT at follow-up were 71%, 65%, and 67%. For 18F-FET PET/CT the numbers were 29%, 100%, and 83%. Additionally, 18F-FDG PET/CT detected a higher number of second malignancies or distant metastases. Conclusions: 18F-FET is no substitute for 18F-FDG. Although it is more specific, too many malignant lesions are missed due to its lower sensitivit

Combined PET/CT-perfusion in patients with head and neck cancers

Objectives: Computed tomography perfusion (CTP) can provide information about angiogenesis and blood-flow characteristics in tumours. [18F]Fluoro-2-deoxy-d-glucose-positron emission tomography/computed tomography (FDG-PET/CT) is one of the major oncological imaging techniques which provides information about viability of the tumour cell and partly also about its aggressiveness. The aim of the study was to investigate the relationship between FDG and CTP data in patients with head and neck cancers. Materials and methods: Forty-one patients with a clinically suspected head and neck cancer were prospectively included. All patients underwent a combined PET/CT with an integrated CTP examination in the area of the head and neck tumour. CTP data (BF, BV and MTT) and PET data (SUVmax, SUVmean, TLG, PETvol) were compared between tumours and (1) healthy contralateral tissue, (2) inflammatory lesions, (3) metastatic lymph nodes, and CTP data and PET data were correlated in tumours. Results: Thirty-five patients had a head and neck cancer. All CTP data were statistically different between tumours, inflammatory lesions, healthy tissue and metastatic lymph nodes; PET/CT data were in part significantly different. CTP and PET parameters were not significantly correlated. Conclusion: CTP and PET parameters were not significantly correlated; thus, the additional CTP values provide additional insights into tumour behaviour and their glycolytic status. Key Points : • Computed tomography perfusion (CTP) can be performed in combined positron emission tomography (PET)/CT. • CTP in addition to PET provides additional insights into tumour behaviour. • CTP can possibly differentiate between head and neck tumours and inflammatory lesions. • PET/CT with integrated CTP is possible without additional contrast medi

COVID-19: Fernunterricht aus Sicht der Mitarbeitenden von Schulen in Deutschland, Österreich und der Schweiz

Im Zuge der Corona-Pandemie wurden weltweit temporären Schulschließungen vorgenommen. Wie funktioniert(e) Bildung in dieser Kri­se? Daten des Schul-Barometers von insgesamt 5.167 Mitarbeitenden an Schulen aus Deutschland, Österreich und der Schweiz ermöglichen einen Einblick in die Rahmenbedingungen von Digitalisierung während des Lehrens und Lernens während der Schulschließung. Die Daten bestätigen den „digital divide“ in den Kompetenzen und Erfahrungen der Lehrkräfte. Lehrkräfte in Österreich und der Schweiz schätzen ihre digitalen Kompetenzen höher ein als deutsche Mitarbeitende. Die technische Ausstattung wird von Befragten aus Österreich und der Schweiz ebenfalls besser eingeschätzt als in Deutschland. Die Kooperation zwischen Mitarbeitenden der Schule selbst sowie mit Eltern und ein stärkerer Fokus auf die Beziehungsebene zu Schüler*innen wird in Zeiten der Krise trotz und wegen der Distanz noch bedeutsamer für Lehre und Lernen. Perspektivisch können aus den Daten des Schul-Barometers Empfehlungen für die „Schule von morgen“ abgeleitet werden

Down regulation of E-Cadherin (ECAD) - a predictor for occult metastatic disease in sentinel node biopsy of early squamous cell carcinomas of the oral cavity and oropharynx

<p>Abstract</p> <p>Background</p> <p>Prognostic factors in predicting occult lymph node metastasis in patients with head and neck squamous-cell carcinoma (HNSCC) are necessary to improve the results of the sentinel lymph node procedure in this tumour type. The E-Cadherin glycoprotein is an intercellular adhesion molecule in epithelial cells, which plays an important role in establishing and maintaining intercellular connections.</p> <p>Objectives</p> <p>To determine the value of the molecular marker E-Cadherin in predicting regional metastatic disease.</p> <p>Methods</p> <p>E-Cadherin expression in tumour tissue of 120 patients with HNSCC of the oral cavity and oropharynx were evaluated using the tissue microarray technique. 110 tumours were located in the oral cavity (91.7%; mostly tongue), 10 tumours in the oropharynx (8.3%). Intensity of E-Cadherin expression was quantified by the Intensity Reactivity Score (IRS). These results were correlated with the lymph node status of biopsied sentinel lymph nodes. Univariate and multivariate analysis was used to determine statistical significance.</p> <p>Results</p> <p>pT-stage, gender, tumour side and location did not correlate with lymph node metastasis. Differentiation grade (<it>p </it>= 0.018) and down regulation of E-Cadherin expression significantly correlate with positive lymph node status (<it>p </it>= 0.005) in univariate and multivariate analysis.</p> <p>Conclusion</p> <p>These data suggest that loss of E-cadherin expression is associated with increased lymhogeneous metastasis of HNSCC. E-cadherin immunohistochemistry may be used as a predictor for lymph node metastasis in squamous cell carcinoma of the oral cavity and oropharynx.</p> <p><b>Level of evidence: 2b</b></p

Status of the BELLE II Pixel Detector

The Belle II experiment at the super KEK B-factory (SuperKEKB) in Tsukuba, Japan, has been collecting $e^+e^−$ collision data since March 2019. Operating at a record-breaking luminosity of up to $4.7×10^{34} cm^{−2}s^{−1}$, data corresponding to $424 fb^{−1}$ has since been recorded. The Belle II VerteX Detector (VXD) is central to the Belle II detector and its physics program and plays a crucial role in reconstructing precise primary and decay vertices. It consists of the outer 4-layer Silicon Vertex Detector (SVD) using double sided silicon strips and the inner two-layer PiXel Detector (PXD) based on the Depleted P-channel Field Effect Transistor (DePFET) technology. The PXD DePFET structure combines signal generation and amplification within pixels with a minimum pitch of $(50×55) μm^2$. A high gain and a high signal-to-noise ratio allow thinning the pixels to $75 μm$ while retaining a high pixel hit efficiency of about $99$. As a consequence, also the material budget of the full detector is kept low at $≈0.21$$\frac{X}{X_0}$ per layer in the acceptance region. This also includes contributions from the control, Analog-to-Digital Converter (ADC), and data processing Application Specific Integrated Circuits (ASICs) as well as from cooling and support structures. This article will present the experience gained from four years of operating PXD; the first full scale detector employing the DePFET technology in High Energy Physics. Overall, the PXD has met the expectations. Operating in the intense SuperKEKB environment poses many challenges that will also be discussed. The current PXD system remains incomplete with only 20 out of 40 modules having been installed. A full replacement has been constructed and is currently in its final testing stage before it will be installed into Belle II during the ongoing long shutdown that will last throughout 2023

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Collins and Sivers asymmetries in muonproduction of pions and kaons off transversely polarised protons

Measurements of the Collins and Sivers asymmetries for charged pions and charged and neutral kaons produced in semi-inclusive deep-inelastic scattering of high energy muons off transversely polarised protons are presented. The results were obtained using all the available COMPASS proton data, which were taken in the years 2007 and 2010. The Collins asymmetries exhibit in the valence region a non-zero signal for pions and there are hints of non-zero signal also for kaons. The Sivers asymmetries are found to be positive for positive pions and kaons and compatible with zero otherwise. © 2015