185 research outputs found

    Hypoxia and hyperglycaemia determine why some endometrial tumours fail to respond to metformin

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    High expression of Ki67, a proliferation marker, is associated with reduced endometrial cancer-specific survival. Pre-surgical metformin reduces tumour Ki-67 expression in some women with endometrial cancer. Metformin's anti-cancer activity may relate to effects on cellular energy metabolism. Since tumour hypoxia and glucose availability are major cellular redox determinants, we evaluated their role in endometrial cancer response to metformin. Endometrial cancer biopsies from women treated with pre-surgical metformin were tested for the hypoxia markers, HIF-1α and CA-9. Endometrial cancer cell lines were treated with metformin in variable glucose concentrations in normoxia or hypoxia and cell viability, mitochondrial biogenesis, function and energy metabolism were assessed. In women treated with metformin (n = 28), Ki-67 response was lower in hypoxic tumours. Metformin showed minimal cytostatic effects towards Ishikawa and HEC1A cells in conventional medium (25 mM glucose). In low glucose (5.5 mM), a dose-dependent cytostatic effect was observed in normoxia but attenuated in hypoxia. Tumours treated with metformin showed increased mitochondrial mass (n = 25), while in cultured cells metformin decreased mitochondrial function. Metformin targets mitochondrial respiration, however, in hypoxic, high glucose conditions, there was a switch to glycolytic metabolism and decreased metformin response. Understanding the metabolic adaptations of endometrial tumours may identify patients likely to derive clinical benefit from metformin

    The prevalence of mismatch repair deficiency in ovarian cancer: A systematic review and meta-analysis

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    This is the final version. Available on open access from Wiley via the DOI in this recordData availability statement: All data contained here within this article is available on request from the corresponding authorOvarian cancer (OC) is the least survivable gynecological malignancy and presents late. Five-year survival for OC is around 45% increasing the need for innovative treatments. Checkpoint inhibitors have shown significant clinical efficacy in mismatch repair deficient (MMRd) cancers and could be a powerful treatment in OC. However, their application in OC is limited due to the lack of data on the prevalence of MMRd. The aim of our study was to conduct a systematic review of the literature and meta-analysis to provide an accurate estimate of the prevalence of MMRd in OC. We followed PRISMA guidelines throughout. Studies were identified by electronic searches of Medline, Embase, Cochrane CENTRAL and Web of Science followed by citation searching. Studies not written in English were excluded. All studies were reviewed by at least two independent reviewers. Proportions of test positivity were calculated by random and fixed-effects meta-analysis models. I2 score was used to assess heterogeneity across studies. In total 54 studies were included with 17 532 analyzed for MMRd. The overall proportions of MMRd by immunohistochemistry and microsatellite instability analysis were 6.7% and 10.4%, respectively. MMRd was reported in all histotypes of epithelial OC but was most common in endometrioid OC. We estimate that on average 46.7% (95% CI: 28.8-65.4) of ovarian carcinomas showing MMRd by IHC had a germline path_MMR variant identified. OC in those with Lynch syndrome seems to present at an earlier age and stage. Studies however were generally of low quality and there was a high degree of heterogeneity. A significant minority (up to 16%) of OC displays MMRd and, therefore, could be amenable to checkpoint inhibition therapy. However, the current literature base is of limited quality and therefore high-quality prospective studies exploring MMRd in OC with the use of multimodal testing are required. In addition, trials researching efficacy of checkpoint inhibition in MMRd OC are needed

    Measuring spirometry in a lung cancer screening cohort highlights possible underdiagnosis and misdiagnosis of Chronic Obstructive Pulmonary Disease

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    Introduction: Chronic Obstructive Pulmonary Disease (COPD) is underdiagnosed, and measurement of spirometry alongside low-dose computed tomography (LDCT) screening for lung cancer is one strategy to increase earlier diagnosis of this disease. // Methods: Ever-smokers at high risk of lung cancer were invited to the Yorkshire Lung Screening Trial for a Lung Health Check (LHC) comprising LDCT screening, pre-bronchodilator spirometry and smoking cessation service. In this cross-sectional study we present data on participant demographics, respiratory symptoms, lung function, emphysema on imaging and both self-reported and primary care diagnoses of COPD. Multivariable logistic regression analysis identified factors associated with possible underdiagnosis and misdiagnosis of COPD in this population, with airflow obstruction (AO) defined as FEV1/FVC ratio <0.70. // Results: Of 3,920 LHC attendees undergoing spirometry, 17% had undiagnosed AO with respiratory symptoms, representing potentially undiagnosed COPD. Compared to those with a primary care COPD code, this population had milder symptoms, better lung function, and were more likely to be current smokers (p≤0.001 for all comparisons). Of 836 attendees with a primary care COPD code who underwent spirometry, 19% did not have AO, potentially representing misdiagnosed COPD, although symptom burden was high. // Discussion: Spirometry offered alongside LDCT screening can potentially identify cases of undiagnosed and misdiagnosed COPD. Future research should assess the downstream impact of these findings to determine if any meaningful changes to treatment and outcomes occurs, and also to assess the impact on co-delivering spirometry on other parameters of LDCT screening performance such as participation and adherence. Additionally, work is needed to better understand the aetiology of respiratory symptoms in those with misdiagnosed COPD, to ensure this highly symptomatic group receive evidence-based interventions

    Yorkshire Lung Screening Trial (YLST): protocol for a randomised controlled trial to evaluate invitation to community-based low-dose CT screening for lung cancer versus usual care in a targeted population at risk

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    © Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY. Published by BMJ. INTRODUCTION: Lung cancer is the world's leading cause of cancer death. Low-dose computed tomography (LDCT) screening reduced lung cancer mortality by 20% in the US National Lung Screening Trial. Here, we present the Yorkshire Lung Screening Trial (YLST), which will address key questions of relevance for screening implementation. METHODS AND ANALYSIS: Using a single-consent Zelen's design, ever-smokers aged 55-80 years registered with a general practice in Leeds will be randomised (1:1) to invitation to a telephone-based risk-assessment for a Lung Health Check or to usual care. The anticipated number randomised by household is 62 980 individuals. Responders at high risk will be invited for LDCT scanning for lung cancer on a mobile van in the community. There will be two rounds of screening at an interval of 2 years. Primary objectives are (1) measure participation rates, (2) compare the performance of PLCOM2012 (threshold ≥1.51%), Liverpool Lung Project (V.2) (threshold ≥5%) and US Preventive Services Task Force eligibility criteria for screening population selection and (3) assess lung cancer outcomes in the intervention and usual care arms. Secondary evaluations include health economics, quality of life, smoking rates according to intervention arm, screening programme performance with ancillary biomarker and smoking cessation studies. ETHICS AND DISSEMINATION: The study has been approved by the Greater Manchester West research ethics committee (18-NW-0012) and the Health Research Authority following review by the Confidentiality Advisory Group. The results will be disseminated through publication in peer-reviewed scientific journals, presentation at conferences and on the YLST website. TRIAL REGISTRATION NUMBERS: ISRCTN42704678 and NCT03750110

    Cost-effectiveness of sentinel lymph node biopsy vs inguinofemoral lymphadenectomy in women with vulval cancer

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    background: This study examines the cost-effectiveness of sentinel lymph node biopsy, a potentially less morbid procedure, compared with inguinofemoral lymphadenectomy (IFL) among women with stage I and stage II vulval squamous cell carcinoma. methods: A model-based economic evaluation was undertaken based on clinical evidence from a systematic review of published sources. A decision tree model was developed with the structure being informed by clinical input, taking the perspective of the health-care provider. results: For overall survival for 2 years, IFL was found to be the most cost-effective option and dominated all other strategies, being the least costly and most effective. For morbidity-free related outcomes for 2 years, sentinel lymph node (SLN) biopsy with 99mTc and blue dye and haematoxylin & eosin (H&E) histopathology, with ultrastaging and immunohistochemistry reserved for those that test negative following H&E is likely to be the most effective approach. conclusion: SLN biopsy using 99mTc and blue dye with ultrastaging may be considered the most cost-effective strategy based on the outcome of survival free of morbidity for 2 years. The findings here also indicate that using blue dye and H&E for the identification of the SLN and the identification of metastasis, respectively, are not sensitive enough to be used on their own

    The Proportion of Endometrial Tumours Associated with Lynch Syndrome (PETALS): a prospective cross-sectional study

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    This is the final version. Available on open access from the Public Library of Science via the DOI in this recordBackground: Lynch syndrome (LS) predisposes to endometrial (EC), colorectal and other cancers through inherited pathogenic variants affecting mismatch-repair (MMR) genes. Diagnosing LS in women with EC can reduce subsequent cancer mortality through colonoscopic surveillance and aspirin chemoprevention; it also enables cascade testing of relatives. A growing consensus supports LS screening in EC, however, the expected proportion of test-positives and optimal testing strategy is uncertain. Previous studies from insurance-based healthcare systems were limited by narrow selection criteria, failure to apply reference standard tests consistently and poor conversion to definitive testing. The aim of this study was to establish the prevalence of LS and the diagnostic accuracy of LS testing strategies in an unselected EC population. Methods and Findings: This was a prospective cross-sectional study carried out at a large UK gynaecological cancer centre between October/2015 and January/2017. Women diagnosed with EC or atypical hyperplasia (AH) were offered LS testing. Tumours underwent MMR immunohistochemistry (IHC), microsatellite instability (MSI) and targeted MLH1-methylation testing. Women <50 years, with strong family histories and/or indicative tumour molecular features underwent MMR germline sequencing. Somatic MMR sequencing was performed when indicative molecular features were unexplained by LS or MLH1-hypermethylation. The main outcome measures were the prevalence of LS in an unselected EC population and the diagnostic accuracy of clinical and tumour testing strategies for risk stratifying women with EC for MMR germline sequencing. In total, 500 women participated in the study; only 2 (<1%) declined. Germline sequencing was indicated and conducted for 136 and 135 women, respectively. 16/500 women (3.2%, 95% CI 1.8% to 5.1%) had LS and 11 more (2.2%) had MMR variants of uncertain significance. Restricting testing to age <50 years, indicative family history (revised Bethesda guidelines or Amsterdam-II criteria) or endometrioid histology alone would have missed 9 (56%), 11 (69%) or 12 (75%), and 5 (31%) of the 16 cases of LS, respectively. In total 132/500 tumours were MMR-deficient by IHC, of which 83/132 (63%) had MLH1-hypermethylation and 16/49 (33%) of the remaining patients had LS (16/132 with MMR-deficiency, 12%). MMR-IHC with targeted MLH1-methylation testing was more discriminatory for LS than MSI/methylation testing, with 100% versus 56.3% (16/16 versus 9/16) sensitivity (p=0.016) and equal 97.5% (468/484) specificity. 64% MSI-H and 73% MMR-deficient tumours unexplained by LS or MLH1-hypermethylation had somatic MMR-mutations. The main limitation of the study was failure to conduct MMR germline sequencing for the whole study population, which means that the sensitivity and specificity of tumour triage strategies for LS detection may be over-estimated, although the risk of LS in women with no clinical or tumour predictors is expected to be extremely low. Conclusions: In this study, we observed that age, family history and histology are imprecise clinical correlates of LS-EC. IHC outperformed MSI for tumour triage, and reliably identified both germline and somatic MMR mutations. The 3.2% proportion of LS-EC is similar to colorectal cancer, supporting unselected screening of EC for LS.
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