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Microbial cell-free DNA (microbial cfDNA) offers a minimally invasive approach for profiling the microbiome. Despite technical and biological challenges, the potential of microbial cfDNA for cancer detection is increasingly being evaluated using deep sequencing, novel laboratory approaches, and computational methods. Targeting the microbiome using liquid biopsies could improve early cancer detection., Competing Interests: Declaration of interests J.C.M.W. is an inventor of patents for methods for ctDNA detection. He is a stockholder and a cofounder of cfdx. He has served as a consultant for Delfi Diagnostics and Cleary Gottlieb. The other authors declare no conflicts of interest., (Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.)

Purpose: Medical students providing support to clinical teams during Covid-19 may have been an opportunity for service and learning. We aimed to understand why the reported educational impact has been mixed to inform future placements., Methods: We conducted a cross-sectional survey of medical students at UK medical schools during the first Covid-19 'lockdown' period in the UK (March-July 2020). Analysis was informed by the conceptual framework of service and learning., Results: 1245 medical students from 37 UK medical schools responded. 57% of respondents provided clinical support across a variety of roles and reported benefits including increased preparedness for foundation year one compared to those who did not ( p  < 0.0001). However, not every individual's experience was equal. For some, roles complemented the curriculum and provided opportunities for clinical skill development, reflection, and meaningful contribution to the health service. For others, the relevance of their role to their education was limited; these roles typically focused on service provision, with few opportunities to develop., Conclusion: The conceptual framework of service and learning can help explain why student experiences have been heterogeneous. We highlight how this conceptual framework can be used to inform clinical placements in the future, in particular the risks, benefits, and structures.[Box: see text].

Purpose: Understanding the factors that influence prosocial behaviour during the COVID-19 pandemic is essential due to the disruption to healthcare provision., Methods: We conducted an in-depth, mixed-methods cross-sectional survey, from 2 May 2020 to 15 June 2020, of medical students at medical schools in the United Kingdom. Data analysis was informed by Latané and Darley's theory of prosocial behaviour during an emergency., Results: A total of 1145 medical students from 36 medical schools responded. Although 947 (82.7%) of students were willing to volunteer, only 391 (34.3%) had volunteered. Of the students, 92.7% understood they may be asked to volunteer; however, we found deciding one's responsibility to volunteer was mitigated by a complex interaction between the interests of others and self-interest. Further, concerns revolving around professional role boundaries influenced students' decisions over whether they had the required skills and knowledge., Conclusion: We propose two additional domains to Latané and Darley's theory that medical students consider before making their final decision to volunteer: 'logistics' and 'safety'. We highlight modifiable barriers to prosocial behaviour and provide suggestions regarding how the conceptual framework can be operationalized within educational strategies to address these barriers. Optimizing the process of volunteering can aid healthcare provision and may facilitate a safer volunteering process. Key messages  What is already known on this topic: There is a discrepancy between the number of students willing to volunteer during pandemics and disasters, and those who actually volunteer. Understanding the factors that influence prosocial behaviour during the current COVID-19 pandemic and future pandemics and disasters is essential. What this study adds: We expanded on Latané and Darley's theory of prosocial behaviour in an emergency and used this to conceptualize students' motivations to volunteer, highlighting a number of modifiable barriers to prosocial behaviour during the COVID-19 pandemic. How this study might affect research, practice, or policy: We provide suggestions regarding how the conceptual framework can be operationalized to support prosocial behaviours during emergencies for the ongoing COVID-19 pandemic and future crises., (© The Author(s) 2023. Published by Oxford University Press on behalf of Postgraduate Medical Journal. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Purpose: Glenoid component loosening is a potential complication of reverse total shoulder arthroplasty (rTSA), occurring in part due to lack of adequate screw purchase in quality scapular bone stock. This study was to determine the efficacy of a surgeon-designed, 3D-printed patient-specific instrumentation (PSI) compared to conventional instrumentation (CI) in achieving longer superior and inferior screw lengths for glenoid component fixation., Methods: A multi-centre retrospective analysis of patients who underwent rTSA between 2015 and 2020. Lengths of the superior and inferior locking screws inserted for fixation of the glenoid baseplate component were recorded and compared according to whether patients received PSI or CI. Secondary outcomes included operative duration and incidence of complications requiring revision surgery., Results: Seventy-three patients (31 PSI vs. 42 CI) were analysed. Average glenoid diameter was 24.5 mm (SD: 3.1) and 81% of patients had smaller glenoid dimensions compared to the baseplate itself. PSI produced significantly longer superior (44.7 vs. 30.7 mm; P < 0.001) and inferior (43.0 vs. 31 mm; P < 0.001) mean screw lengths, as compared to CI. A greater proportion of maximal screw lengths for the given rTSA construct (48 mm) were observed in the PSI group (71.9% vs. 11.9% superior, 59.4% vs. 11.9% inferior). Operative duration was not statistically significantly different between the PSI and CI groups (150 min vs. 169 min, respectively; P = 0.229). No patients had radiographic loosening of the glenoid component with an average of 2-year follow-up., Conclusion: PSI facilitates longer superior and inferior screw placement in the fixation of the glenoid component for rTSA. With sufficient training, PSI can be designed and implemented by surgeons themselves., (© 2023. The Author(s).)

Mutational signatures accumulate in somatic cells as an admixture of endogenous and exogenous processes that occur during an individual's lifetime. Since dividing cells release cell-free DNA (cfDNA) fragments into the circulation, we hypothesize that plasma cfDNA might reflect mutational signatures. Point mutations in plasma whole genome sequencing (WGS) are challenging to identify through conventional mutation calling due to low sequencing coverage and low mutant allele fractions. In this proof of concept study of plasma WGS at 0.3-1.5x coverage from 215 patients and 227 healthy individuals, we show that both pathological and physiological mutational signatures may be identified in plasma. By applying machine learning to mutation profiles, patients with stage I-IV cancer can be distinguished from healthy individuals with an Area Under the Curve of 0.96. Interrogating mutational processes in plasma may enable earlier cancer detection, and might enable the assessment of cancer risk and etiology., (© 2022. The Author(s).)

Detection of minimal residual disease in patients with cancer, who are in complete remission with no cancer cells detectable, has the potential to improve recurrence-free survival through treatment selection. Studies analyzing circulating tumor DNA (ctDNA) in patients with solid tumors suggest the potential to accurately predict and detect relapse, enabling treatment strategies that may improve clinical outcomes. Over the past decade, assays for ctDNA detection in plasma samples have steadily increased in sensitivity and specificity. These are applied for the detection of residual disease after treatment and for earlier detection of recurrence. Novel clinical trials are now assessing how assays for "residual disease and recurrence" (RDR) may influence current treatment paradigms and potentially change the landscape of risk classification for cancer recurrence. In this review, we appraise the progress of RDR detection using ctDNA and consider the emerging role of liquid biopsy in the monitoring and management of solid tumors., Competing Interests: Declaration of interests J.C.M.W. and N.R. are inventors/contributors on patents covering methods for ctDNA detection (including WO/2020/104670). P.R. reports institutional research funding from Novartis, Grail/Illumina, ArcherDx/Invitae, Inivata, Epic Sciences, and Tempus; advisory board/honoraria from Novartis, AstraZeneca, Foundation Medicine, Pfizer, Epic Sciences, Inivata, and Natera; and consulting for Tempus. Y.-S.Y. reports honoraria/consultancy from Novartis, Lilly, Pfizer, AstraZeneca, Eisai, MSD, and Specialised Therapeutics and travel support from Pfizer, Eisai, and Roche. S.-J.D. has received research funding from Roche Genentech and Cancer Therapeutics (CTx) CRC and has been an advisory board member for AstraZeneca and Inivata. S.K. serves on the advisory board and is a consultant for Inivata and Natera. N.R. and C.D.M. are officers of Inivata. T.I.M., P.R., E.L.M., R.G., I.T., Y.-S.Y., W.A.R., B.B., A.B., and J.T. served on the advisory board and consulted for Inivata., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Importance: Novel therapies for SARS-CoV-2 infection are urgently needed. Antineoplastic compounds that target cellular machinery used by SARS-CoV-2 for entry and replication, including angiotensin-converting enzyme 2 (ACE2), may disrupt SARS-CoV-2 activity., Objectives: To determine whether patients with cancer treated with potential ACE2-lowering antineoplastic compounds exhibit lower SARS-CoV-2 infection rates., Design, Setting, and Participants: We used the Library of Integrated Network-Based Cellular Signatures database to identify antineoplastic compounds associated with decreased ACE2 gene expression across cell lines. We then evaluated a retrospective cohort of 1701 patients who were undergoing antineoplastic therapy at Memorial Sloan Kettering Cancer Center in New York, New York, during the COVID-19 pandemic to determine if treatment with an ACE2-lowering antineoplastic was associated with a decreased odds ratio (OR) of SARS-CoV-2 infection. Patients included in the analysis underwent active treatment for cancer and received a SARS-CoV-2 test between March 10 and May 28, 2020., Main Outcome and Measure: The association between potential ACE2-lowering antineoplastic treatment and a positive SARS-CoV-2 test., Results: In the cohort of 1701 patients, SARS-CoV-2 infection rates were determined for 949 (55.8%) female and 752 (44.2%) male patients (mean [SD] age, 63.1 [13.1] years) with diverse cancers receiving antineoplastic therapy. In silico analysis of gene expression signatures after drug treatment identified 91 compounds associated with downregulation of ACE2 across cell lines. Of the total cohort, 215 (12.6%) patients were treated with 8 of these compounds, including 3 mTOR/PI3K inhibitors and 2 antimetabolites. In a multivariable analysis of patients who received an ACE2-lowering antineoplastic adjusting for confounders, 15 of 215 (7.0%) patients had a positive SARS-CoV-2 test compared with 191 of 1486 (12.9%) patients who received other antineoplastic therapies (OR, 0.53; 95% CI, 0.29-0.88). Findings were confirmed in additional sensitivity analyses including cancer type, steroid use, and a propensity-matched subcohort. Gemcitabine treatment was associated with reduced SARS-CoV-2 infection (OR, 0.42; 95% CI, 0.17-0.87)., Conclusions and Relevance: In this cohort study, in silico analysis of drug-associated gene expression signatures identified potential ACE2-lowering antineoplastic compounds, including mTOR/PI3K inhibitors and antimetabolites. Patients who received these compounds exhibited statistically significantly lower rates of SARS-CoV-2 infection compared with patients given other antineoplastics. Further evaluation of the biological and clinical anti-SARS-CoV-2 properties of identified antineoplastic compounds is warranted.

Objective: This systematic review aimed to estimate the willingness of students to volunteer during a disaster, and how well-prepared medical students are for volunteering by assessing their knowledge and medical school curriculum of disaster and pandemic medicine., Results: A total of 37 studies met inclusion criteria including 11 168 medical students and 91 medical schools. 24 studies evaluated knowledge (64.9%), 16 evaluated volunteering (43.2%) and 5 evaluated medical school curricula (13.5%). Weighted mean willingness to volunteer during a disaster was 68.4% (SD=21.7%, range=26.7%-87.8%, n=2911), and there was a significant difference between those planning to volunteer and those who actually volunteered (p<0.0001). We identified a number of modifiable barriers which may contribute to this heterogeneity. Overall, knowledge of disasters was poor with a weighted mean of 48.9% (SD=15.1%, range=37.1%-87.0%, n=2985). 36.8% of 76 medical schools curricula included teaching on disasters. However, students only received minimal teaching (2-6 hours)., Conclusions: This study demonstrates that there is a large number of students who are willing to volunteer during pandemics. However, they are unlikely to be prepared for these roles as overall knowledge is poor, and this is likely due to minimal teaching on disasters at medical school. During the current COVID-19 pandemic and in future disasters, medical students may be required to volunteer as auxiliary staff. There is a need to develop infrastructure to facilitate this process as well as providing education and training to ensure students are adequately prepared to perform these roles safely., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2021. No commercial re-use. See rights and permissions. Published by BMJ.)

Glioma-derived cell-free DNA (cfDNA) is challenging to detect using liquid biopsy because quantities in body fluids are low. We determined the glioma-derived DNA fraction in cerebrospinal fluid (CSF), plasma, and urine samples from patients using sequencing of personalized capture panels guided by analysis of matched tumor biopsies. By sequencing cfDNA across thousands of mutations, identified individually in each patient's tumor, we detected tumor-derived DNA in the majority of CSF (7/8), plasma (10/12), and urine samples (10/16), with a median tumor fraction of 6.4 × 10 -3 , 3.1 × 10 -5 , and 4.7 × 10 -5 , respectively. We identified a shift in the size distribution of tumor-derived cfDNA fragments in these body fluids. We further analyzed cfDNA fragment sizes using whole-genome sequencing, in urine samples from 35 glioma patients, 27 individuals with non-malignant brain disorders, and 26 healthy individuals. cfDNA in urine of glioma patients was significantly more fragmented compared to urine from patients with non-malignant brain disorders (P = 1.7 × 10 -2 ) and healthy individuals (P = 5.2 × 10 -9 ). Machine learning models integrating fragment length could differentiate urine samples from glioma patients (AUC = 0.80-0.91) suggesting possibilities for truly non-invasive cancer detection., (© 2021 The Authors. Published under the terms of the CC BY 4.0 license.)

Background: The coronavirus disease 2019 pandemic has led to global disruption of healthcare. Many students volunteered to provide clinical support. Volunteering to work in a clinical capacity was a unique medical education opportunity; however, it is unknown whether this was a positive learning experience or which volunteering roles were of most benefit to students., Methods: The COVIDReady2 study is a national cross-sectional study of all medical students at medical schools in the United Kingdom. The primary outcome is to explore the experiences of medical students who volunteered during the pandemic in comparison to those who did not. We will compare responses to determine the educational benefit and issues they faced. In addition to quantitative analysis, thematic analysis will be used to identify themes in qualitative responses., Discussion: There is a growing body of evidence to suggest that service roles have potential to enhance medical education; yet, there is a shortage of studies able to offer practical advice for how these roles may be incorporated in future medical education. We anticipate that this study will help to identify volunteer structures that have been beneficial for students, so that similar infrastructures can be used in the future, and help inform medical education in a non-pandemic setting., Trial Registration: Not Applicable.

Clinical imaging methods, such as computed tomography (CT), are used for routine tumor response monitoring. Imaging can also reveal intratumoral, intermetastatic, and interpatient heterogeneity, which can be quantified using radiomics. Circulating tumor DNA (ctDNA) in the plasma is a sensitive and specific biomarker for response monitoring. Here we evaluated the interrelationship between circulating tumor DNA mutant allele fraction (ctDNA maf ), obtained by targeted amplicon sequencing and shallow whole genome sequencing, and radiomic measurements of CT heterogeneity in patients with stage IV melanoma. ctDNA maf and radiomic observations were obtained from 15 patients with a total of 70 CT examinations acquired as part of a prospective trial. 26 of 39 radiomic features showed a significant relationship with log(ctDNA maf ). Principal component analysis was used to define a radiomics signature that predicted ctDNA maf independent of lesion volume. This radiomics signature and serum lactate dehydrogenase were independent predictors of ctDNA maf . Together, these results suggest that radiomic features and ctDNA maf may serve as complementary clinical tools for treatment monitoring.

Circulating tumor-derived DNA (ctDNA) can be used to monitor cancer dynamics noninvasively. Detection of ctDNA can be challenging in patients with low-volume or residual disease, where plasma contains very few tumor-derived DNA fragments. We show that sensitivity for ctDNA detection in plasma can be improved by analyzing hundreds to thousands of mutations that are first identified by tumor genotyping. We describe the INtegration of VAriant Reads (INVAR) pipeline, which combines custom error-suppression methods and signal-enrichment approaches based on biological features of ctDNA. With this approach, the detection limit in each sample can be estimated independently based on the number of informative reads sequenced across multiple patient-specific loci. We applied INVAR to custom hybrid-capture sequencing data from 176 plasma samples from 105 patients with melanoma, lung, renal, glioma, and breast cancer across both early and advanced disease. By integrating signal across a median of >10 5 informative reads, ctDNA was routinely quantified to 1 mutant molecule per 100,000, and in some cases with high tumor mutation burden and/or plasma input material, to parts per million. This resulted in median area under the curve (AUC) values of 0.98 in advanced cancers and 0.80 in early-stage and challenging settings for ctDNA detection. We generalized this method to whole-exome and whole-genome sequencing, showing that INVAR may be applied without requiring personalized sequencing panels so long as a tumor mutation list is available. As tumor sequencing becomes increasingly performed, such methods for personalized cancer monitoring may enhance the sensitivity of cancer liquid biopsies., (Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)

Background: Studies report that survival outcomes in patients with non-muscle-invasive bladder cancer (NMIBC) are worse when cystectomy is delayed. However, no systematic evidence is available., Objective: The aim of this study was to systematically review the literature to compare the long-term survival outcomes of patients with high-grade NMIBC (T1G3, including carcinoma in situ) who have early cystectomy compared to deferred radical cystectomy post-diagnosis., Materials and Methods: A systematic review was carried out by searching MEDLINE and related databases (Google Scholar, National Health Service Evidence) for all relevant studies published from 1946 to present. Additional studies were identified through following the references of relevant papers. Studies were included if they met the following criteria: inclusion of at least 30 patients having high-grade NMIBC, 2 groups treated with either early or deferred cystectomy with a clear temporal cut-off between groups and reported data on survival rate of at least 5 years., Results: Literature was systematically reviewed, and 10 studies were included, totaling 1,516 patients who underwent either primary cystectomy or deferred cystectomy. It was found that patients who underwent early cystectomy show improved 5- to 10-year cancer-specific survival (relative risk = 0.81, p = 0.029) suggesting a significant survival benefit when compared to deferred cystectomy., Conclusions: This study provides systematically gathered evidence showing benefit of early cystectomy. Despite this result, radical cystectomy greatly impairs quality of life and represents overtreatment for a significant minority. This result highlights the importance of a decisive treatment plan to minimize treatment delay., (Copyright © 2020 by S. Karger AG, Basel.)

This article was migrated. The article was marked as recommended. During the COVID-19 pandemic, early graduation of senior medical students simultaneously offers useful clinical experience in preparation for junior doctor posts, whilst helping address staffing shortages due to illness or self-isolation. Having recently graduated early from medical school, we offer our reflections on the obstacles and opportunities associated with working in an uncharted clinical environment. We are not the only ones on a steep learning curve at this time: this pandemic will challenge and provide learning for staff of all levels., (Copyright: © 2020 Alexander L et al.)

Background: Recent advances in the study and clinical applications of circulating tumor DNA (ctDNA) are limited by practical considerations of sample collection. Whole-genome sequencing (WGS) is increasingly used for analysis of ctDNA, identifying copy-number alterations and fragmentation patterns. We hypothesized that low-depth/shallow WGS (sWGS) data may be generated from minute amounts of cell-free DNA, and that fragment-size selection may remove contaminating genomic DNA from small blood volumes. Dried blood spots have practical advantages for sample collection, may facilitate serial sampling, and could support novel study designs in humans and animal models., Methods: We developed a protocol for the isolation and analysis of cell-free DNA from dried blood spots using filter paper cards and bead-based size selection. DNA extracted and size-selected from dried spots was analyzed using sWGS and polymerase chain reaction (PCR)., Results: Analyzing a 50 μL dried blood spot from frozen whole blood of a patient with melanoma, we identified ctDNA based on the presence of tumor-specific somatic copy-number alterations, and found a fragment-size profile similar to that observed in plasma DNA. We found alterations in different chromosomes in blood spots from 2 patients with high-grade serous ovarian carcinoma. Extending this approach to serial dried blood spots from mouse xenograft models, we detect tumor-derived cell-free DNA and identified ctDNA from the originally grafted ascites., Conclusion: Our data suggest that ctDNA can be detected and monitored in dried blood spots from archived and fresh blood samples, enabling new approaches for sample collection and novel study/trial designs for both patients and in vivo models., (© American Association for Clinical Chemistry 2020.)

Background: Cell-free tumor-derived DNA (ctDNA) allows non-invasive monitoring of cancers, but its utility in renal cell cancer (RCC) has not been established., Methods: Here, a combination of untargeted and targeted sequencing methods, applied to two independent cohorts of patients (n = 91) with various renal tumor subtypes, were used to determine ctDNA content in plasma and urine., Results: Our data revealed lower plasma ctDNA levels in RCC relative to other cancers of similar size and stage, with untargeted detection in 27.5% of patients from both cohorts. A sensitive personalized approach, applied to plasma and urine from select patients (n = 22) improved detection to ~ 50%, including in patients with early-stage disease and even benign lesions. Detection in plasma, but not urine, was more frequent amongst patients with larger tumors and in those patients with venous tumor thrombus. With data from one extensively characterized patient, we observed that plasma and, for the first time, urine ctDNA may better represent tumor heterogeneity than a single tissue biopsy. Furthermore, in a subset of patients (n = 16), longitudinal sampling revealed that ctDNA can track disease course and may pre-empt radiological identification of minimal residual disease or disease progression on systemic therapy. Additional datasets will be required to validate these findings., Conclusions: These data highlight RCC as a ctDNA-low malignancy. The biological reasons for this are yet to be determined. Nonetheless, our findings indicate potential clinical utility in the management of patients with renal tumors, provided improvement in isolation and detection approaches.

Background: Both Vitamin D deficiency and magnesium deficiency have an increased prevalence and have been associated with an increased risk of and increased severity of symptoms in both depression and schizophrenia (Boerman 2016, Tarleton & Littenberg 2015). This effect appears more pronounced in younger populations and is often apparent from the time of initial diagnosis and is present with adjustment for confounding factors. Thus, the evidence suggests that Vitamin D and magnesium deficiency reflects not only dietary or somatic aspects of health but also may have a role in the pathophysiology of depression and schizophrenia., Subjects and Methods: A single site audit of serum Vitamin D and magnesium levels in patients at an Acute Day Treatment Unit was carried out. Blood tests were performed on admission and analysed in house. Data were collected between April - June 2019 and was analysed subsequently, as described below (n=73)., Results: Our data show that our psychiatric day treatment unit cohort (n=73) had a higher proportion of vitamin D deficiency (52%) than the general population (40%), although due to the limited sample size this was not significant (p=0.22, Chi-squared test). The percentage of patients who were magnesium deficient was 78.6% (n=22/28). However, the F60 subgroup of patients with personality disorders showed a high prevalence of vit D deficiency (p=0.07), highlighting a trend towards significance despite the limited size of this subgroup., Conclusions: We carried out a single-site audit of serum vitamin D and magnesium levels in a psychiatric day unit population in order to assess the extent of vitamin deficiency in such patients. These data indicate that that the proportion of patients with vitamin D deficiency is higher than in the general population. Further larger analysis is needed to establish the statistical significance of these data and whether treatment with vitamin D supplementation improves outcomes.

Although serial tumor assessments are increasingly performed through imaging and molecular approaches, such evaluations are often considered in isolation, as robust frameworks for integrating multiple biomarkers are currently lacking. Thus, in this issue of Cell, Kurtz et al. present a method (termed CIRI) that integrates pre-treatment and on-treatment risk factors for accurate outcome prediction., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Existing methods to improve detection of circulating tumor DNA (ctDNA) have focused on genomic alterations but have rarely considered the biological properties of plasma cell-free DNA (cfDNA). We hypothesized that differences in fragment lengths of circulating DNA could be exploited to enhance sensitivity for detecting the presence of ctDNA and for noninvasive genomic analysis of cancer. We surveyed ctDNA fragment sizes in 344 plasma samples from 200 patients with cancer using low-pass whole-genome sequencing (0.4×). To establish the size distribution of mutant ctDNA, tumor-guided personalized deep sequencing was performed in 19 patients. We detected enrichment of ctDNA in fragment sizes between 90 and 150 bp and developed methods for in vitro and in silico size selection of these fragments. Selecting fragments between 90 and 150 bp improved detection of tumor DNA, with more than twofold median enrichment in >95% of cases and more than fourfold enrichment in >10% of cases. Analysis of size-selected cfDNA identified clinically actionable mutations and copy number alterations that were otherwise not detected. Identification of plasma samples from patients with advanced cancer was improved by predictive models integrating fragment length and copy number analysis of cfDNA, with area under the curve (AUC) >0.99 compared to AUC <0.80 without fragmentation features. Increased identification of cfDNA from patients with glioma, renal, and pancreatic cancer was achieved with AUC > 0.91 compared to AUC < 0.5 without fragmentation features. Fragment size analysis and selective sequencing of specific fragment sizes can boost ctDNA detection and could complement or provide an alternative to deeper sequencing of cfDNA., (Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)

Purpose Effective clinical leadership is crucial to avoid failings in the delivery of safe health care, particularly during a period of increasing scrutiny and cost-constraints for the National Health Service (NHS). However, there is a paucity of leadership training for health-care students, the future leaders of the NHS, which is due in part to overfilled curricula. The purpose of this study was to assess the impact of student-led leadership training for the benefit of fellow students. Design/methodology/approach To address this training gap, a group of multiprofessional students organised a series of large-group seminars and small-group workshops given by notable health-care leaders at a London university over the course of two consecutive years. Findings The majority of students had not previously received any formal exposure to leadership training. Feedback post-events were almost universally positive, though students expressed a preference for experiential teaching of leadership. Working with university faculty, an inaugural essay prize was founded and student members were given the opportunity to complete internships in real-life quality improvement projects. Originality/value Student-led teaching interventions in leadership can help to fill an unmet teaching need and help to better equip the next generation of health-care workers for future roles as leaders within the NHS.

Background and Purpose: To evaluate the tolerability and maximum tolerated dose (MTD) of sorafenib administered concurrently with palliative radiotherapy., Material and Methods: In patients with incurable cancer, sorafenib was escalated independently in three cohorts based on irradiation site: thorax, abdomen or pelvis. Sorafenib was administered days 1-28 and radiotherapy (30Gy in 10 fractions) was delivered days 8-12 and 15-19. Dose-limiting toxicities (DLT) were acute grade 3+ toxicities attributable to radiotherapy., Results: For the thorax, abdomen and pelvis cohorts, 14, 16 and 4 patients were recruited, and Dose Levels 3, 3 and 2 were reached, respectively. Sorafenib-related systemic toxicity led to significant sorafenib interruption in 10 patients. There were 3 DLTs in total, one per cohort: grade 3 oesophagitis (thoracic), transaminase elevation (abdominal) and grade 5 bowel perforation (pelvic; patient with tumour invading bowel). Grade 2 radiation dermatitis developed in 12 patients. The trial was terminated early as slow accrual and sorafenib-related systemic toxicity prevented efficient evaluation of RT-related DLTs., Conclusions: The MTD of sorafenib when used with 30Gy in 10 fractions was not established due to sorafenib-related systemic toxicity. Severe radiotherapy-related toxicities were also observed. These events suggest this concurrent combination does not warrant further study., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Improvements in genomic and molecular methods are expanding the range of potential applications for circulating tumour DNA (ctDNA), both in a research setting and as a 'liquid biopsy' for cancer management. Proof-of-principle studies have demonstrated the translational potential of ctDNA for prognostication, molecular profiling and monitoring. The field is now in an exciting transitional period in which ctDNA analysis is beginning to be applied clinically, although there is still much to learn about the biology of cell-free DNA. This is an opportune time to appraise potential approaches to ctDNA analysis, and to consider their applications in personalized oncology and in cancer research.

Type II methanotrophs produce polyhydroxybutyrate (PHB), while Type I methanotrophs do not. A laboratory-scale fluidized bed reactor was initially inoculated with a Type II Methylocystis-like dominated culture. At elevated levels of dissolved oxygen (DO, 9 mg/L), pH of 6.2-6.5 with nitrate as the N-source, a Methylobacter-like Type I methanotroph became dominant within the biofilms which did not produce PHB. A shift to biofilms capable of PHB production was achieved by re-inoculating with Type II Methylosinus culture, providing dissolved N(2) as the N-source, and maintaining a low influent DO (2.0mg/L). The resulting biofilms contained both Types I and II methanotrophs. Batch tests indicated that biofilm samples grown with N(2) became dominated by Type II methanotrophs and produced PHB. Enrichments with nitrate or ammonium were dominated by Type I methanotrophs without PHB production capability. The key selection factors favoring Type II were N(2) as N-source and low DO., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Superior vena cava syndrome is a common complication of malignancy. The epidemiology, presentation, and diagnostic evaluation of patients presenting with the syndrome are reviewed. Management options including chemotherapy and radiation therapy and the role of endovascular stents are discussed along with the evidence for each of the therapeutic options., (Copyright 2010 Elsevier Inc. All rights reserved.)

Superior vena cava syndrome (SVCS) is a common complication of malignancy. The epidemiology, presentation, and diagnostic evaluation of patients presenting with the syndrome are reviewed. Management options including chemotherapy and radiation therapy (RT) and the role of endovascular stents are discussed along with the evidence for each of the therapeutic options.

Introduction: Approximately one quarter of all cancer patients will require palliative radiation treatment at some point during the course of their disease, but only a minority of these patients are entered in clinical trials., Ethical Assessment of Biomarkers in Palliative Radiotherapy Trials: We review the literature debating the ethics of inclusion of "palliative" patients on clinical trials. We suggest that these patients provide a potentially valuable resource that can be leveraged to facilitate the discovery and validation of biomarkers predictive of radiation response and toxicity. In addition, this patient population offers valuable opportunities to test combination of radiation and targeted therapies to screen for activity, toxicity and biomarkers in a relatively safe manner., Conclusion: Patients undergoing palliative radiation therapy may provide new opportunities for the development and testing of predictive radiotherapy biomarkers as well as affording opportunities to test combinations of radiation and targeted therapies.

We describe a technique for the MTT assay that irradiates all cells at once by a combination of couch movement and a step-and-shoot irradiation technique on a linear accelerator with 6 MV and 18 MV photon beams. In two experimental setups, we obtained maximum to minimum dose ranges of 10 for the constant MU/bin (monitor units per bin) setup and 20 for the variable MU/bin technique. The irradiation technique described is dose rate independent and it can be used on any teletherapy irradiation machine. We also employed radiochromic film dosimetry to verify dose delivered in each of the wells within the dish. It is shown that for the lowest doses, relative dose variation within wells reaches a value of 6%. We also demonstrated that the radiochromic film positioned below the 96-well plate does not underestimate dose deposited within each compartment by more than 2% due to the vertical dose gradient.