11 research outputs found
Fully Automatic Danger Zone Determination for SBRT in NSCLC
Lung cancer is the major cause of cancer death worldwide. The most common form of lung cancer is non-small cell lung cancer(NSCLC). Stereotactic body radiation therapy (SBRT) has emerged as a good alternative to surgery in patients with peripheralstage I NSCLC, demonstrating favorable tumor control and low toxicity. Due to spatial relationship to several critical organs atrisk, SBRT of centrally located lesions is associated with more severe toxicity and requires modification in dose application andfractionation, which is currently evaluated in clinical trials. Therefore a classification of lung tumors into central or peripheralis required. In this work we present a novel, highly versatile, mulitmodality tool for tumor classification which requires no userinteraction. Furthermore the tool can automatically segment the trachea, proximal bronchial tree, mediastinum, gross target volumeand internal target volume. The proposed work is evaluated on 19 cases with different image modalities assessing segmentationquality as well as classification accuracy. Experiments showed a good segmentation quality and a classification accuracy of 95 %.These results suggest the use of the proposed tool for clinical trials to assist clinicians in their work and to fasten up the workflowin NSCLC patients treatment
Cell-Free DNA Genomic Profiling and Its Clinical Implementation in Advanced Prostate Cancer.
Most men with prostate cancer (PCa), despite potentially curable localized disease at initial diagnosis, progress to metastatic disease. Despite numerous treatment options, choosing the optimal treatment for individual patients remains challenging. Biomarkers guiding treatment sequences in an advanced setting are lacking. To estimate the diagnostic potential of liquid biopsies in guiding personalized treatment of PCa, we evaluated the utility of a custom-targeted next-generation sequencing (NGS) panel based on the AmpliSeq HD Technology. Ultra-deep sequencing on plasma circulating free DNA (cfDNA) samples of 40 metastatic castration-resistant PCa (mCRPC) and 28 metastatic hormone-naive PCa (mCSPC) was performed. CfDNA somatic mutations were detected in 48/68 (71%) patients. Of those 68 patients, 42 had matched tumor and cfDNA samples. In 21/42 (50%) patients, mutations from the primary tumor tissue were detected in the plasma cfDNA. In 7/42 (17%) patients, mutations found in the primary tumor were not detected in the cfDNA. Mutations from primary tumors were detected in all tested mCRPC patients (17/17), but only in 4/11 with mCSPC. AR amplifications were detected in 12/39 (31%) mCRPC patients. These results indicate that our targeted NGS approach has high sensitivity and specificity for detecting clinically relevant mutations in PCa
Effect of high-dose glucocorticoid treatment on human brown adipose tissue activity: a randomised, double-blinded, placebo-controlled cross-over trial in healthy men
BACKGROUND
Glucocorticoids (GCs) are widely applied anti-inflammatory drugs that are associated with adverse metabolic effects including insulin resistance and weight gain. Previous research indicates that GCs may negatively impact brown adipose tissue (BAT) activity in rodents and humans.
METHODS
We performed a randomised, double-blinded cross-over trial in 16 healthy men (clinicaltrials.govNCT03269747). Participants received 40 mg of prednisone per day for one week or placebo. After a washout period of four weeks, participants crossed-over to the other treatment arm. Primary endpoint was the increase in resting energy expenditure (EE) in response to a mild-cold stimulus (cold-induced thermogenesis, CIT). Secondary outcomes comprised mean F-FDG uptake into supraclavicular BAT (SUV) as determined by FDG-PET/CT, volume of the BAT depot as well as fat content determined by MRI. The plasma metabolome and the transcriptome of supraclavicular BAT and of skeletal muscle biopsies after each treatment period were analysed.
FINDINGS
Sixteen participants were recruited to the trial and completed it successfully per protocol. After prednisone treatment resting EE was higher both during warm and cold conditions. However, CIT was similar, 153 kcal/24 h (95% CI 40-266 kcal/24 h) after placebo and 186 kcal/24 h (95% CI 94-277 kcal/24 h, p = 0.38) after prednisone. SUV of BAT after cold exposure was not significantly affected by prednisone (3.36 g/ml, 95% CI 2.69-4.02 g/ml, vs 3.07 g/ml, 95% CI 2.52-3.62 g/ml, p = 0.28). Results of plasma metabolomics and BAT transcriptomics corroborated these findings. RNA sequencing of muscle biopsies revealed higher expression of genes involved in calcium cycling. No serious adverse events were reported and adverse events were evenly distributed between the two treatments.
INTERPRETATION
Prednisone increased EE in healthy men possibly by altering skeletal muscle calcium cycling. Cold-induced BAT activity was not affected by GC treatment, which indicates that the unfavourable metabolic effects of GCs are independent from thermogenic adipocytes.
FUNDING
Grants from Swiss National Science Foundation (PZ00P3_167823), Bangerter-Rhyner Foundation and from Nora van der Meeuwen-Häfliger Foundation to MJB. A fellowship-grant from the Swiss National Science Foundation (SNF211053) to WS. Grants from German Research Foundation (project number: 314061271-TRR 205) and Else Kröner-Fresenius (grant support 2012_A103 and 2015_A228) to MR
Comparison of [; 18; F]FDG PET/CT with magnetic resonance imaging for the assessment of human brown adipose tissue activity
Brown adipose tissue (BAT) is a thermogenic tissue which can generate heat in response to mild cold exposure. As it constitutes a promising target in the fight against obesity, we need reliable techniques to quantify its activity in response to therapeutic interventions. The current standard for the quantification of BAT activity is [; 18; F]FDG PET/CT. Various sequences in magnetic resonance imaging (MRI), including those measuring its relative fat content (fat fraction), have been proposed and evaluated in small proof-of-principle studies, showing diverging results. Here, we systematically compare the predictive value of adipose tissue fat fraction measured by MRI to the results of [; 18; F]FDG PET/CT.; We analyzed the diagnostic reliability of MRI measured fat fraction (FF) for the estimation of human BAT activity in two cohorts of healthy volunteers participating in two prospective clinical trials (NCT03189511, NCT03269747). In both cohorts, BAT activity was stimulated by mild cold exposure. In cohort 1, we performed [; 18; F]FDG PET/MRI; in cohort 2, we used [; 18; F]FDG PET/CT followed by MRI. Fat fraction was determined by 2-point Dixon and 6-point Dixon measurement, respectively. Fat fraction values were compared to SUV; mean; in the corresponding tissue depot by simple linear regression.; In total, 33 male participants with a mean age of 23.9 years and a mean BMI of 22.8 kg/m; 2; were recruited. In 32 participants, active BAT was visible. On an intra-individual level, FF was significantly lower in high-SUV areas compared to low-SUV areas (cohort 1: p < 0.0001 and cohort 2: p = 0.0002). The FF of the supraclavicular adipose tissue depot was inversely related to its metabolic activity (SUVmean) in both cohorts (cohort 1: R; 2; = 0.18, p = 0.09 and cohort 2: R; 2; = 0.42, p = 0.009).; MRI FF explains only about 40% of the variation in BAT glucose uptake. Thus, it can currently not be used to substitute [; 18; F] FDG PET-based imaging for quantification of BAT activity.; ClinicalTrials.gov. NCT03189511 , registered on June 17, 2017, actual study start date was on May 31, 2017, retrospectively registered. NCT03269747 , registered on September 01, 2017