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A dynamic mutational landscape associated with an inter-regionally diverse immune response in malignant rhabdoid tumour

Malignant rhabdoid tumour (MRT) is a childhood neoplasm of high malignancy characterised by biallelic mutation and/or loss of the epigenetic master regulator SMARCB1, accompanied by no or few other oncogenic drivers. In spite of their generally low mutational burden, an intratumoural T-cell response has been reported in a subset of MRTs, indicating that immune checkpoint inhibition may be consider

Solvability and complex limit bicharacteristics

We shall study the solvability of pseudodifferential operators which are not of principal type. The operator will have complex principal symbol satisfying condition (Ψ) and we shall consider the limits of semibicharacteristics at the set where the principal symbol vanishes of at least second order. The convergence shall be as smooth curves, and we shall assume that the normalized complex Hamilton

Hypoxic-Ischemic Encephalopathy Evaluated by Brain Autopsy and Neuroprognostication after Cardiac Arrest

Importance: Neuroprognostication studies are potentially susceptible to a self-fulfilling prophecy as investigated prognostic parameters may affect withdrawal of life-sustaining therapy. Objective: To compare the results of prognostic parameters after cardiac arrest (CA) with the histopathologically determined severity of hypoxic-ischemic encephalopathy (HIE) obtained from autopsy results. Design,

Impact of beam angle choice on pencil beam scanning breath-hold protontherapy for lung lesions

Introduction:The breath-hold technique inter alia has been suggested to mitigate the detrimental effect of motion on pencil beam scanned (PBS) proton therapy dose distributions. The aim of this study was to evaluate the robustness of incident proton beam angles to day-to-day anatomical variations in breath-hold.Materials and methods: Single field PBS plans at five degrees increments in the transve

Visual outcome, endocrine function and tumor control after fractionated stereotactic radiation therapy of craniopharyngiomas in adults : findings in a prospective cohort

Background: The purpose of this study was to examine visual outcome, endocrine function and tumor control in a prospective cohort of craniopharyngioma patients, treated with fractionated stereotactic radiation therapy (FSRT). Material and methods: Sixteen adult patients with craniopharyngiomas were eligible for analysis. They were treated with linear accelerator-based FSRT during 1999–2015. In all

Patterns of failure for patients with glioblastoma following O-(2-[18F]fluoroethyl)-L-tyrosine PET- and MRI-guided radiotherapy

Background and purpose To evaluate the patterns of failure following clinical introduction of amino-acid O-(2-[18F]fluoroethyl)-L-tyrosine (FET)-PET-guided target definition for radiotherapy (RT) of glioblastoma patients. Materials and methods The first 66 consecutive patients with confirmed histology, scanned using FET-PET/CT and MRI were selected for evaluation. Chemo-radiotherapy was delivered

Liquid fiducial marker applicability in proton therapy of locally advanced lung cancer

Background and purpose We investigated the clinical applicability of a novel liquid fiducial marker (LFM) for image-guided pencil beam scanned (PBS) proton therapy (PBSPT) of locally advanced lung cancer (LALC). Materials and methods The relative proton stopping power (RSP) of the LFM was calculated and measured. Dose perturbations of the LFM and three solid markers, in a phantom, were measured. P

Prognostic value of 18F-FET PET imaging in re-irradiation of high-grade glioma : Results of a phase I clinical trial

Background and purpose Positron emission tomography (PET) provides quantitative metabolic information and potential biomarkers of treatment outcome. We aimed to determine the prognostic value of early 18F-fluoroethyl-tyrosine (18F-FET) PET scans acquired during re-irradiation for recurrent high-grade glioma (HGG). Material and methods A phase I clinical trial of re-irradiation of HGG was carried o

Prospective assessment of the quality of life before, during and after image guided intensity modulated radiotherapy for prostate cancer

Background: Radiotherapy (RT) in combination with androgen deprivation therapy (ADT) for prostate cancer (PCa) carries a risk of gastrointestinal (GI) and genitourinary toxicity, which might affect the quality of life (QoL). The purpose of this study was to assess the QoL in patients with PCa before, during and after radiotherapy (RT) and to compare the QoL 1 year after RT to a normal population.

Robustness of the Voluntary Breath-Hold Approach for the Treatment of Peripheral Lung Tumors Using Hypofractionated Pencil Beam Scanning Proton Therapy

Purpose The safe clinical implementation of pencil beam scanning (PBS) proton therapy for lung tumors is complicated by the delivery uncertainties caused by breathing motion. The purpose of this feasibility study was to investigate whether a voluntary breath-hold technique could limit the delivery uncertainties resulting from interfractional motion. Methods and Materials Data from 15 patients with

A generative model for segmentation of tumor and organs-at-risk for radiation therapy planning of glioblastoma patients

We present a fully automated generative method for simultaneous brain tumor and organs-at-risk segmentation in multi-modal magnetic resonance images. The method combines an existing whole-brain segmentation technique with a spatial tumor prior, which uses convolutional restricted Boltzmann machines to model tumor shape. The method is not tuned to any specific imaging protocol and can simultaneousl

Injectable silver nanosensors:: In vivo dosimetry for external beam radiotherapy using positron emission tomography

Development of safe and efficient radiotherapy routines requires quantification of the delivered absorbed dose to the cancer tissue in individual patients. In vivo dosimetry can provide accurate information about the absorbed dose delivered during treatment. In the current study, a novel silver-nanosensor formulation based on poly(vinylpyrrolidinone)-coated silver nanoparticles formulated in a gel

A dosimetric comparison of real-time adaptive and non-adaptive radiotherapy : A multi-institutional study encompassing robotic, gimbaled, multileaf collimator and couch tracking

Purpose A study of real-time adaptive radiotherapy systems was performed to test the hypothesis that, across delivery systems and institutions, the dosimetric accuracy is improved with adaptive treatments over non-adaptive radiotherapy in the presence of patient-measured tumor motion. Methods and materials Ten institutions with robotic(2), gimbaled(2), MLC(4) or couch tracking(2) used common mater

Validation and Calibration of the EXIT89 Evacuation Model for Road Tunnel Evacuation Applications

The validation of an evacuation model is generally performed through testing its predictive capabilities within a set of standard environments (e.g. buildings) or standard layouts. Unfortunately, non-expert users could consider model results as reliable in unique environments as well, such as road tunnels, and extend their use to applications where no ad hoc validation tests have been performed. T

Comprehensive molecular comparison of BRCA1 hypermethylated and BRCA1 mutated triple negative breast cancers

Homologous recombination deficiency (HRD) is a defining characteristic in BRCA-deficient breast tumors caused by genetic or epigenetic alterations in key pathway genes. We investigated the frequency of BRCA1 promoter hypermethylation in 237 triple-negative breast cancers (TNBCs) from a population-based study using reported whole genome and RNA sequencing data, complemented with analyses of genetic

Sweden’s constitution decides its exceptional Covid-19 policy

The Swedish policy response to Covid-19 is exceptional by international comparison. This column explains how the approach is decided by three articles in the Swedish constitution. The first guarantees the freedom of movement for Swedish citizens, ruling out nationwide lockdowns. The second establishes unique independence for public agencies, allowing them to design the policy response to the pandeThe Swedish policy response to Covid-19 is exceptional by international comparison. This column explains how the approach is decided by three articles in the Swedish constitution. The first guarantees the freedom of movement for Swedish citizens, ruling out nationwide lockdowns. The second establishes unique independence for public agencies, allowing them to design the policy response to the pande