Search

Background: Association between the single nucleotide polymorphism rs3218536 (known as Arg188His) located in the X-ray repair cross complementing group 2 (XRCC2) gene and cancer susceptibility has been widely investigated. However, results thus far have remained controversial. A meta-analysis was performed to identify the impact of this polymorphism on cancer susceptibility. Methods: PubMed and Embase databases were searched systematically until September 7, 2013 to obtain all the records evaluating the association between the XRCC2 Arg188His polymorphism and the risk of all types of cancers. We used the odds ratio (OR) as measure of effect, and pooled the data in a Mantel-Haenszel weighed random-effects meta-analysis to provide a summary estimate of the impact of this polymorphism on breast cancer, ovarian cancer and other cancers. All the analyses were carried out in STATA 12.0. Results: With 30868 cases and 38656 controls, a total of 45 case-control studies from 26 publications were eventually included in our meta-analysis. No significant association was observed between the XRCC2 Arg188His polymorphism and breast cancer susceptibility (dominant model: OR = 0.94, 95%CI = 0.86–1.04, P = 0.232). However, a significant impact of this polymorphism was detected on decreased ovarian cancer risk (dominant model: OR = 0.83, 95%CI = 0.73–0.95, P = 0.007). In addition, we found this polymorphism was associated with increased upper aerodigestive tract (UADT) cancer susceptibility (dominant model: OR = 1.51, 95%CI = 1.04–2.20, P = 0.032). Conclusion: The Arg188His polymorphism might play different roles in carcinogenesis of various cancer types. Current evidence did not suggest that this polymorphism was directly associated with breast cancer susceptibility. However, this polymorphism might contribute to decreased gynecological cancer risk and increased UADT cancer risk. More preclinical and epidemiological studies were still imperative for further evaluation. [ABSTRACT FROM AUTHOR]

Previous studies have reported inconsistent associations between platelet count (PLT) and cancer survival. However, whether there is linear causal effect merits in-depth investigations. We conducted a cohort study using the UK Biobank and a two-sample Mendelian randomization (MR) analysis. PLT levels were measured prior to cancer diagnosis. We adopted overall survival (OS) as the primary outcome. Cox models were utilized to estimate the effects of PLTs on survival outcomes at multiple lag times for cancer diagnosis. We employed 34 genetic variants as PLT proxies for MR analysis. Linear and non-linear effects were modeled. Prognostic effects of gene expression harboring the instrumental variants were also investigated. A total of 65 471 cancer patients were included. We identified a significant association between elevated PLTs (per 100 × 10 9 /L) and inferior OS (HR: 1.07; 95% CI: 1.04-1.10; p  < .001). Similar significant associations were observed for several cancer types. We further observed a U-shaped relationship between PLTs and cancer survival ( p  < .001). Our MR analysis found null evidence to support a causal association between PLTs and overall cancer survival (HR: 1.000; 95% CI: 0.998-1.001; p  = .678), although non-linear MR analysis unveiled a potential greater detrimental effect at lower PLT range. Expression of eleven PLT-related genes were associated with cancer survival. Early detection of escalated PLTs indicated possible occult cancer development and inferior subsequent survival outcomes. The observed associations could potentially be non-linear. However, PLT is less likely to be a promising therapeutic target.

Background: The authors aimed to comprehensively evaluate the efficacy and safety of antibiotic prophylaxis through surgical and nonsurgical scenarios and assess the strength of evidence., Materials and Methods: The authors performed an umbrella review of meta-analyses of randomized controlled trials (RCTs). An evidence map was created to summarize the absolute benefits of antibiotic prophylaxis in each scenario and certainty of evidence., Results: Seventy-five meta-analyses proved eligible with 725 RCTs and 78 clinical scenarios in surgical and medical prophylaxis. Of 119 health outcomes, 67 (56.3%) showed statistically significant benefits, 34 of which were supported by convincing or highly suggestive evidence from RCTs. For surgeries, antibiotic prophylaxis may minimize infection occurrences in most surgeries except Mohs surgery, simple hand surgery, herniorrhaphy surgery, hepatectomy, thyroid surgery, rhinoplasty, stented distal hypospadias repair, midurethral sling placement, endoscopic sinus surgery, and transurethral resection of bladder tumors with only low to very low certainty evidence. For nonsurgery invasive procedures, only low to very low certainty evidence showed benefits of antibiotic prophylaxis for cystoscopy, postoperative urinary catheterization, and urodynamic study. For medical prophylaxis, antibiotic prophylaxis showed greater benefits in nonemergency scenarios, in which patients were mainly with weakened immune systems, or at risk of recurrent chronic infections. Antibiotics prophylaxis may increase antibiotic resistance or other adverse events in most scenarios and reached significance in cystoscopy, afebrile neutropenia following chemotherapy and hematopoietic stem cell transplantation., Conclusions: Antibiotic prophylaxis in surgical and nonsurgical scenarios is generally effective and seems independent of surgical cleanliness and urgency of diseases. Its safety is not well determined due to lack of available data. Nevertheless, the low quality of current evidence limits the external validity of these findings, necessitating clinicians to judiciously assess indications, balancing low infection rates with antibiotic-related side effects., (Copyright © 2023 The Author(s). Published by Wolters Kluwer Health, Inc.)

We aimed to develop and validate prediction models incorporating demographics, clinical features, and a weighted genetic risk score (wGRS) for individual prediction of colorectal cancer (CRC) risk in patients with gastroenterological symptoms. Prediction models were developed with internal validation [CRC Cases: n = 1686/Controls: n = 963]. Candidate predictors included age, sex, BMI, wGRS, family history, and symptoms (changes in bowel habits, rectal bleeding, weight loss, anaemia, abdominal pain). The baseline model included all the non-genetic predictors. Models A (baseline model + wGRS) and B (baseline model) were developed based on LASSO regression to select predictors. Models C (baseline model + wGRS) and D (baseline model) were built using all variables. Models' calibration and discrimination were evaluated through the Hosmer-Lemeshow test (calibration curves were plotted) and C-statistics (corrected based on 1000 bootstrapping). The models' prediction performance was: model A (corrected C-statistic = 0.765); model B (corrected C-statistic = 0.753); model C (corrected C-statistic = 0.764); and model D (corrected C-statistic = 0.752). Models A and C, that integrated wGRS with demographic and clinical predictors, had a statistically significant improved prediction performance. Our findings suggest that future application of genetic predictors holds significant promise, which could enhance CRC risk prediction. Therefore, further investigation through model external validation and clinical impact is merited.

Background: Total neoadjuvant therapy is a promising treatment for locally advanced rectal cancer, utilizing either short-course radiotherapy or long-course chemoradiotherapy, but their relative efficacy remains unclear. The aim of this Bayesian network meta-analysis was to investigate clinical outcomes amongst patients receiving total neoadjuvant therapy with short-course radiotherapy or long-course chemoradiotherapy, and those receiving long-course chemoradiotherapy alone., Methods: A systematic literature search was performed. All studies that compared at least two of these three treatments for locally advanced rectal cancer were included. The primary endpoint was the pathological complete response rate, and survival outcomes were adopted as secondary outcomes., Results: Thirty cohorts were included. Compared with long-course chemoradiotherapy, both total neoadjuvant therapy with long-course chemoradiotherapy (OR 1.78, 95 per cent c.i. 1.43 to 2.26) and total neoadjuvant therapy with short-course radiotherapy (OR 1.75, 95 per cent c.i. 1.23 to 2.50) improved the pathological complete response rate. Similar benefits were observed in the sensitivity and subgroup analyses, except for short-course radiotherapy with one to two cycles of chemotherapy. No significant differences in survival outcomes were found amongst the three treatments. Long-course chemoradiotherapy with consolidation chemotherapy (HR 0.44, 95 per cent c.i. 0.20 to 0.99) exhibited higher disease-free survival than long-course chemoradiotherapy alone., Conclusion: Compared with long-course chemoradiotherapy, both short-course radiotherapy with greater than or equal to three cycles of chemotherapy and total neoadjuvant therapy with long-course chemoradiotherapy can improve the pathological complete response rate, and long-course chemoradiotherapy with consolidation chemotherapy may lead to a marginal benefit in disease-free survival. The pathological complete response rate and survival outcomes are similar for total neoadjuvant therapy with short-course radiotherapy or long-course chemoradiotherapy., (© The Author(s) 2023. Published by Oxford University Press on behalf of BJS Society Ltd. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Learning classification models in practice usually requires numerous labeled data for training. However, instance-based annotation can be inefficient for humans to perform. In this article, we propose and study a new type of human supervision that is fast to perform and useful for model learning. Instead of labeling individual instances, humans provide supervision to data regions , which are subspaces of the input data space, representing subpopulations of data. Since labeling now is performed on a region level, 0/1 labeling becomes imprecise. Thus, we design the region label to be a qualitative assessment of the class proportion, which coarsely preserves the labeling precision but is also easy for humans to do. To identify informative regions for labeling and learning, we further devise a hierarchical active learning process that recursively constructs a region hierarchy. This process is semisupervised in the sense that it is driven by both active learning strategies and human expertise, where humans can provide discriminative features. To evaluate our framework, we conducted extensive experiments on nine datasets as well as a real user study on a survival analysis of colorectal cancer patients. The results have clearly demonstrated the superiority of our region-based active learning framework against many instance-based active learning methods.

Objective: To estimate the global and regional prevalence and cases of abdominal aortic aneurysms (AAAs) in 2019 and to evaluate major associated factors., Background: Understanding the global prevalence of AAA is essential for optimizing health services and reducing mortality from reputed AAA., Methods: PubMed, MEDLINE, and Embase were searched for articles published until October 11, 2021. Population-based studies that reported AAA prevalence in the general population, defined AAA as an aortic diameter of 30 mm or greater with ultrasonography or computed tomography. A multilevel mixed-effects meta-regression approach was used to establish the relation between age and AAA prevalence for high-demographic sociodemographic index and low-and middle-sociodemographic index countries. Odds ratios of AAA associated factors were pooled using a random-effects method., Results: We retained 54 articles across 19 countries. The global prevalence of AAA among persons aged 30 to 79 years was 0.92% (95% CI, 0.65-1.30), translating to a total of 35.12 million (95% CI, 24.94-49.80) AAA cases in 2019. Smoking, male sex, family history of AAA, advanced age, hypertension, hypercholesterolemia, obesity, cardiovascular disease, cerebrovascular disease, claudication, peripheral artery disease, pulmonary disease, and renal disease were associated with AAA. In 2019, the Western Pacific region had the highest AAA prevalence at 1.31% (95% CI, 0.94-1.85), whereas the African region had the lowest prevalence at 0.33% (95% CI, 0.23-0.48)., Conclusions: A substantial proportion of people are affected by AAA. There is a need to optimize epidemiological studies to promptly respond to at-risk and identified cases to improve outcomes., Competing Interests: The authors report no conflicts of interest., (Copyright © 2022 The Author(s). Published by Wolters Kluwer Health, Inc.)

Epigenetics plays an important role in regulating stem cell signaling, as well as in the oncogenesis of lung cancer and therapeutic resistance. Determining how to employ these regulatory mechanisms to treat cancer is an intriguing medical challenge. Lung cancer is caused by signals that cause aberrant differentiation of stem cells or progenitor cells. The different pathological subtypes of lung cancer are determined by the cells of origin. Additionally, emerging studies have demonstrated that the occurrence of cancer treatment resistance is connected to the hijacking of normal stem cell capability by lung cancer stem cells, especially in the processes of drug transport, DNA damage repair, and niche protection. In this review, we summarize the principles of the epigenetic regulation of stem cell signaling in relation to the emergence of lung cancer and resistance to therapy. Furthermore, several investigations have shown that the tumor immune microenvironment in lung cancer affects these regulatory pathways. And ongoing experiments on epigenetics-related therapeutic strategies provide new insight for the treatment of lung cancer in the future., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Wu, Feng, Zhang, He, Xu, Wang and Li.)

N6-methyladenosine (m6A) modification has been demonstrated to exhibit a crucial prognostic effect on colorectal cancer (CRC). Nonetheless, potential mechanism of m6A in survival rate and immunotherapeutic response remains unknown. Here we investigated the genes associated with m6A regulators and developed a risk score for predicting the overall survival (OS) of CRC patients. RNA-seq transcriptomic profiling data of COAD/READ samples were obtained from The Cancer Genome Atlas (TCGA) database. Absolute Shrinkage and Selection Operator (LASSO)- Cox regression analysis was conducted to identify the m6A-related gene expression signatures and the selected genes were inputted into stepwise regression to develop a prognostic risk score in TCGA, and its predictive performance of CRC survival was further validated in Gene Expression Omnibus (GEO) datasets. According to our results, the risk score comprising 18 m6A-related mRNAs was significantly associated with CRC survival in both TCGA and GEO datasets. And the stratified analysis also confirmed that high-risk score acted as a poor factor in different age, sex, T stage, and tumour, node, metastasis (TNM) stages. The m6A-related prognostic score in combination with clinical characteristics yielded time-dependent area under the receiver operating characteristic curve (AUCs) of 0.85 (95%CI: 0.79-0.91), 0.84 (95%CI: 0.79-0.90) and 0.80 (95%CI: 0.71-0.88) for the prediction of the 1-, 3-, 5-year OS of CRC in TCGA cohort. Furthermore, mutation of oncogenes occurred more frequently in the high-risk group and the composition of immune cells in tumour microenvironment (TME) was significantly distinct between the low- and high-risk groups. The low-risk group had a lower microsatellite instability (MSI) score, T-cell exclusion score and dysfunction score, implying that low-risk patients may have a better immunotherapy response than high-risk patients. In summary, a prognostic risk score derived from m6A-related gene expression signatures could serve as a potential prognostic predictor for CRC survival and indicator for predicting immunotherapy response in CRC patients., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The reviewer ZZ declared a shared parent affiliation with the author(s) CL to the handling editor at the time of review., (Copyright © 2023 Yu, Wang, Sun, Zhou, Hu, Hu, He, Lin, Chen, Xu, Dunlop, Theodoratou, Ding and Li.)

Background: Diverticular disease has been inconsistently associated with colorectal cancer risk. We conducted a bidirectional Mendelian randomization study to assess this association., Methods: Forty-three and seventy single-nucleotide polymorphisms associated with diverticular disease and colorectal cancer at the genome-wide significance level (p < 5 × 10 - 8 ) were selected as instrumental variables from large-scale genome-wide association studies of European descent, respectively. Summary-level data for colon cancer, rectum cancer, and colorectal cancer were obtained from genome-wide association analyses of the FinnGen consortium and the UK Biobank study. Summary-level data for diverticular disease was derived from a genome-wide association study conducted in the UK Biobank population. The random effect inverse-variance weighted Mendelian randomization approach was used as the primary method and MR-Egger, weighted-median, and MR-PRESSO approaches were conducted as sensitivity analyses., Results: Genetically determined diverticular disease was associated with a higher risk of colorectal cancer (beta = 0.441, 95%CI: 0.081-0.801, P = 0.016) in the FinnGen population, but the association was not found in the UK Biobank (beta = 0.208, 95%CI: -0.291,0.532, P = 0.207). The positive association remained consistent direction in the three sensitivity analyses. In the stratified analysis in the FinnGen consortium, an association was found to exist between genetically predicted diverticular disease and colon cancer (beta = 0.489, 95%CI: 0.020-0.959, P = 0.041), rather than rectum cancer (beta = 0.328, 95%CI: -0.119-0.775, P = 0.151). Besides, we found a slight association between colorectal cancer and diverticular disease (beta = 0.007, 95%CI: 0.004-0.010, P < 0.001) when using colorectal cancer as exposome and diverticular disease as outcome. However, there is a large sample overlap in this step of analysis., Conclusion: This Mendelian randomization study suggests that diverticular disease may be a possible risk factor for colorectal cancer and colon cancer rather than rectum cancer in the FinnGen population., (© 2023. The Author(s).)

Background: Approximately 10% of stage I colorectal cancer (CRC) patients experience unfavorable clinical outcomes after surgery. However, little is known about the subset of stage I patients who are predisposed to high risk of recurrence or death. Previous evidence was limited by small sample sizes and lack of validation., Methods: We aimed to identify early indicators and develop a risk stratification model to inform prognosis of stage I patients by employing two large prospective cohorts. Prognostic factors for stage II tumors, including T stage, number of nodes examined, preoperative carcinoma embryonic antigen (CEA), lymphovascular invasion, perineural invasion (PNI), and tumor grade were investigated in the discovery cohort, and significant findings were further validated in the other cohort. We adopted disease-free survival (DFS) as the primary outcome for maximum statistical power and recurrence rate and overall survival (OS) as secondary outcomes. Hazard ratios (HRs) were estimated from Cox proportional hazard models, which were subsequently utilized to develop a multivariable model to predict DFS. Predictive performance was assessed in relation to discrimination, calibration and net benefit., Results: A total of 728 and 413 patients were included for discovery and validation. Overall, 6.7% and 4.1% of the patients developed recurrences during follow-up. We identified consistent significant effects of PNI and higher preoperative CEA on inferior DFS in both the discovery (PNI: HR = 4.26, 95% CI: 1.70-10.67, p = 0.002; CEA: HR = 1.46, 95% CI: 1.13-1.87, p = 0.003) and the validation analysis (PNI: HR = 3.31, 95% CI: 1.01-10.89, p = 0.049; CEA: HR = 1.58, 95% CI: 1.10-2.28, p = 0.014). They were also significantly associated with recurrence rate. Age at diagnosis was a prominent determinant of OS. A prediction model on DFS using Age at diagnosis, CEA, PNI, and number of LYmph nodes examined (ACEPLY) showed significant discriminative performance (C-index: 0.69, 95% CI:0.60-0.77) in the external validation cohort. Decision curve analysis demonstrated added clinical benefit of applying the model for risk stratification., Conclusions: PNI and preoperative CEA are useful indicators for inferior survival outcomes of stage I CRC. Identification of stage I patients at high risk of recurrence is feasible using the ACEPLY model, although the predictive performance is yet to be improved., (© 2022. The Author(s).)

Alcohol intake is thought to be a risk factor for breast cancer, but the causal relationship and carcinogenic mechanisms are not clear. We performed an up-to-date meta-analysis of prospective studies to assess observational association, and then conducted MR analysis to make causal inference based on the genetic predisposition to alcohol consumption ("drinks per week") and pathological drinking behaviours ("alcohol use disorder" and "problematic alcohol use"), as well as genetically predicted DNA methylation at by alcohol-related CpG sites in blood. We found an observational dose-response association between alcohol intake and breast cancer incidence with an additional risk of 4% for per 10 g/day increase in alcohol consumption. Genetic predisposition to alcohol consumption ("drinks per week") was not causally associated with breast cancer incidence at the OR of 1.01 (95% CI 0.84, 1.23), but problematic alcohol use (PAU) was linked to a higher breast cancer risk at the OR of 1.76 (95% CI 1.04, 2.99) when conditioning on alcohol consumption. Epigenetic MR analysis identified four CpG sites, cg03260624 near CDC7 gene, cg10816169 near ZNF318 gene, cg03345232 near RIN3 gene, and cg26312998 near RP11-867G23.13 gene, where genetically predicted epigenetic modifications were associated with an increased breast cancer incidence risk. Our findings re-affirmed that alcohol consumption is of high risk for breast cancer incidence even at a very low dose, and the pathogenic effect of alcohol on breast cancer could be due to pathological drinking behaviour and epigenetic modification at several CpG sites, which could be potential intervention targets for breast cancer prevention., (© 2022. The Author(s).)

Background: SARS-CoV-2, the causal agent of COVID-19, enters human cells using the ACE2 (angiotensin-converting enzyme 2) protein as a receptor. ACE2 is thus key to the infection and treatment of the coronavirus. ACE2 is highly expressed in the heart and respiratory and gastrointestinal tracts, playing important regulatory roles in the cardiovascular and other biological systems. However, the genetic basis of the ACE2 protein levels is not well understood., Methods: We have conducted the largest genome-wide association meta-analysis of plasma ACE2 levels in >28 000 individuals of the SCALLOP Consortium (Systematic and Combined Analysis of Olink Proteins). We summarize the cross-sectional epidemiological correlates of circulating ACE2. Using the summary statistics-based high-definition likelihood method, we estimate relevant genetic correlations with cardiometabolic phenotypes, COVID-19, and other human complex traits and diseases. We perform causal inference of soluble ACE2 on vascular disease outcomes and COVID-19 severity using mendelian randomization. We also perform in silico functional analysis by integrating with other types of omics data., Results: We identified 10 loci, including 8 novel, capturing 30% of the heritability of the protein. We detected that plasma ACE2 was genetically correlated with vascular diseases, severe COVID-19, and a wide range of human complex diseases and medications. An X-chromosome cis-protein quantitative trait loci-based mendelian randomization analysis suggested a causal effect of elevated ACE2 levels on COVID-19 severity (odds ratio, 1.63 [95% CI, 1.10-2.42]; P =0.01), hospitalization (odds ratio, 1.52 [95% CI, 1.05-2.21]; P =0.03), and infection (odds ratio, 1.60 [95% CI, 1.08-2.37]; P =0.02). Tissue- and cell type-specific transcriptomic and epigenomic analysis revealed that the ACE2 regulatory variants were enriched for DNA methylation sites in blood immune cells., Conclusions: Human plasma ACE2 shares a genetic basis with cardiovascular disease, COVID-19, and other related diseases. The genetic architecture of the ACE2 protein is mapped, providing a useful resource for further biological and clinical studies on this coronavirus receptor.

Background: Substantial evidence indicates that dysbiosis of the gut microbial community is associated with colorectal neoplasia. This review aims to systematically summarise the microbial markers associated with colorectal neoplasia and to assess their predictive performance., Methods: A comprehensive literature search of MEDLINE and EMBASE databases was performed to identify eligible studies. Observational studies exploring the associations between microbial biomarkers and colorectal neoplasia were included. We also included prediction studies that constructed models using microbial markers to predict CRC and adenomas. Risk of bias for included observational and prediction studies was assessed., Results: Forty-five studies were included to assess the associations between microbial markers and colorectal neoplasia. Nine faecal microbiotas (i.e., Fusobacterium, Enterococcus, Porphyromonas, Salmonella, Pseudomonas, Peptostreptococcus, Actinomyces, Bifidobacterium and Roseburia), two oral pathogens (i.e., Treponema denticola and Prevotella intermedia) and serum antibody levels response to Streptococcus gallolyticus subspecies gallolyticus were found to be consistently associated with colorectal neoplasia. Thirty studies reported prediction models using microbial markers, and 83.3% of these models had acceptable-to-good discrimination (AUROC > 0.75). The results of predictive performance were promising, but most of the studies were limited to small number of cases (range: 9-485 cases) and lack of independent external validation (76.7%)., Conclusions: This review provides insight into the evidence supporting the association between different types of microbial species and their predictive value for colorectal neoplasia. Prediction models developed from case-control studies require further external validation in high-quality prospective studies. Further studies should assess the feasibility and impact of incorporating microbial biomarkers in CRC screening programme., (© 2022. The Author(s).)

Background: Associations between colorectal cancer (CRC) and other health outcomes have been reported, but these may be subject to biases, or due to limitations of observational studies., Methods: We set out to determine whether genetic predisposition to CRC is also associated with the risk of other phenotypes. Under the phenome-wide association study (PheWAS) and tree-structured phenotypic model (TreeWAS), we studied 334,385 unrelated White British individuals (excluding CRC patients) from the UK Biobank cohort. We generated a polygenic risk score (PRS) from CRC genome-wide association studies as a measure of CRC risk. We performed sensitivity analyses to test the robustness of the results and searched the Danish Disease Trajectory Browser (DTB) to replicate the observed associations., Results: Eight PheWAS phenotypes and 21 TreeWAS nodes were associated with CRC genetic predisposition by PheWAS and TreeWAS, respectively. The PheWAS detected associations were from neoplasms and digestive system disease group (e.g. benign neoplasm of colon, anal and rectal polyp and diverticular disease). The results from the TreeWAS corroborated the results from the PheWAS. These results were replicated in the observational data within the DTB., Conclusions: We show that benign colorectal neoplasms share genetic aetiology with CRC using PheWAS and TreeWAS methods. Additionally, CRC genetic predisposition is associated with diverticular disease., (© 2021. The Author(s).)

Objective: To identify potential bias in non-inferiority design of published cancer trials, and to provide suggestions for future practice., Study Design and Setting: We systematically searched MEDLINE, Embase and CENTRAL databases (until April 17, 2020) to obtain non-inferiority phase III cancer trials and protocols. Distribution of essential characteristics and study design parameters was compared between trials with and without concluding non-inferiority using multivariable logistic regression., Results: A total of 291 eligible trials were included. We observed that increased odds of concluding non-inferiority was significantly associated with more lenient non-inferiority margins (OR = 1•94, 95% CI 1•02-3•69) and higher hypothesized event rate (OR = 1•24, 95% CI 1•06-1•47). Trials that established non-inferiority adopted margins that were more dispersedly distributed (dispersion OR = 2•90, 95% CI 1•88-4.48)., Conclusion: Although limited by the exploratory nature, our study demonstrated existence of possible distorted non-inferiority design which could incur excess non-inferiority in cancer clinical trials. Pre-registration and transparent reporting of detailed non-inferiority design is imperative for future research., (Copyright © 2021. Published by Elsevier Inc.)

A growing body of evidence suggests that vitamin D deficiency has been associated with an increased susceptibility to viral and bacterial respiratory infections. In this study, we aimed to examine the association between vitamin D and COVID-19 risk and outcomes. We used logistic regression to identify associations between vitamin D variables and COVID-19 (risk of infection, hospitalisation and death) in 417,342 participants from UK Biobank. We subsequently performed a Mendelian Randomisation (MR) study to look for evidence of a causal effect. In total, 1746 COVID-19 cases (399 deaths) were registered between March and June 2020. We found no significant associations between COVID-19 infection risk and measured 25-OHD levels after adjusted for covariates, but this finding is limited by the fact that the vitamin D levels were measured on average 11 years before the pandemic. Ambient UVB was strongly and inversely associated with COVID-19 hospitalization and death overall and consistently after stratification by BMI and ethnicity. We also observed an interaction that suggested greater protective effect of genetically-predicted vitamin D levels when ambient UVB radiation is stronger. The main MR analysis did not show that genetically-predicted vitamin D levels are causally associated with COVID-19 risk (OR = 0.77, 95% CI 0.55-1.11, P = 0.160), but MR sensitivity analyses indicated a potential causal effect (weighted mode MR: OR = 0.72, 95% CI 0.55-0.95, P = 0.021; weighted median MR: OR = 0.61, 95% CI 0.42-0.92, P = 0.016). Analysis of MR-PRESSO did not find outliers for any instrumental variables and suggested a potential causal effect (OR = 0.80, 95% CI 0.66-0.98, p-val = 0.030). In conclusion, the effect of vitamin D levels on the risk or severity of COVID-19 remains controversial, further studies are needed to validate vitamin D supplementation as a means of protecting against worsened COVID-19., (© 2021. The Author(s).)

Background: Better understanding of SARS-CoV-2 transmission risks is needed to support decision-making around mitigation measures for COVID-19 in schools., Methods: We updated a living systematic review and meta-analysis to investigate the extent of SARS-CoV-2 transmission in schools. In this update we modified our inclusion criteria to include: 1) cohort studies; 2) cross-sectional studies that investigated and cross-assessed SARS-COV-2 positivity rates in schools and communities; and 3) pre-post studies. We performed risk of bias evaluation for all included studies using the Newcastle-Ottawa Scale (NOS)., Results: 6270 articles were retrieved and six new studies were added in this update. In total from the two updates and using the new inclusion criteria, we identified 11 cohort studies (1 st update: n = 5; 2 nd update: n = 6) and one cross-sectional study (1 st update: n = 1; 2 nd update: n = 0). We performed a meta-analysis on nine of the 11 cohort studies investigating IAR in schools. Nine cohort studies reported a total of 91 student and 52 staff index cases that exposed 5698 contacts with 101 secondary infections (overall infection attack rate (IAR) = 1.45%, 95% CI = 0.31%-3.26%). IARs for students and school staff were 1.66% (95% CI = 0.08%-4.78%) and 1.18% (95% CI = 0.00%-4.43%) respectively. The risk of bias was found to be high for most studies identified, limiting the confidence in results., Conclusions: There is limited high-quality evidence available to quantify the extent of SARS-CoV-2 transmission in schools or to compare it to community transmission. Emerging evidence suggests the overall IAR and SARS-CoV-2 positivity rate in school settings are low. Higher IAR were found in students, compared to staff., Note: This article is a living systematic review that will be updated to reflect emerging evidence. This is the second version of the original article published on 23 December 2020 (J Glob Health 2020;11:021104), and previous versions can be found as data supplements. When citing this paper please consider adding the version number and date of access for clarity., Competing Interests: Competing interests: The authors completed the ICMJE Unified Competing Interest form (available upon request from the corresponding author), and declare no conflicts of interest., (Copyright © 2021 by the Journal of Global Health. All rights reserved.)

Objective: Accumulating evidence suggests that cancer survivors may have a relatively higher risk of stroke. The aim of this meta-analysis was to determine whether cancer survivors have a relatively higher risk of stroke than cancer-free populations on the basis of published data from population-based cohort studies., Methods: PubMed, Embase, and Cochrane Library were searched from inception to February 8, 2020, for population-based cohort studies. Effect estimates with 95% confidence intervals (CIs) were pooled using the random-effects model. We conducted subgroup analyses and meta-regression to explore sources of heterogeneity and the stability of the results., Results: Twenty population-based cohort studies involving 10,479,530 participants were identified. Overall, the relative risk (RR) for stroke in cancer survivors was 1.66 (95% CI 1.35-2.04; p < 0.001) compared with that in cancer-free controls; survivors of head and neck, hematologic, lung, pancreas, and stomach cancer (all p < 0.05) showed consistently significant results, whereas no significant increased risk was observed for patients with other cancer types. The effects were more prominent in cancer survivors with female sex (RR 1.38, 95% CI 1.18-1.61; p < 0.001), younger age at cancer diagnosis (<45 years) (RR 2.57, 95% CI 1.27-5.19; p = 0.009), and shorter cancer survival duration (≥1-2 years) (RR 1.69, 95% CI 1.18-2.42; p = 0.004). Moreover, cancer survivors had a significantly increased risk of ischemic stroke (RR 1.53, 95% CI 1.28-1.84; p < 0.001) compared with hemorrhagic stroke., Conclusions: Cancer plays a critical role in the etiologic of stroke. Due to the existence of substantial heterogeneity among the included studies, the results should be interpreted with caution. However, early prevention and effective intervention of stroke in cancer survivors require attention from health policy makers., (© 2020 American Academy of Neurology.)

Objective: To provide an understanding of the role of common genetic variations in colorectal cancer (CRC) risk, we report an updated field synopsis and comprehensive assessment of evidence to catalogue all genetic markers for CRC (CRCgene2)., Design: We included 869 publications after parallel literature review and extracted data for 1063 polymorphisms in 303 different genes. Meta-analyses were performed for 308 single nucleotide polymorphisms (SNPs) in 158 different genes with at least three independent studies available for analysis. Scottish, Canadian and Spanish data from genome-wide association studies (GWASs) were incorporated for the meta-analyses of 132 SNPs. To assess and classify the credibility of the associations, we applied the Venice criteria and Bayesian False-Discovery Probability (BFDP). Genetic associations classified as 'positive' and 'less-credible positive' were further validated in three large GWAS consortia conducted in populations of European origin., Results: We initially identified 18 independent variants at 16 loci that were classified as 'positive' polymorphisms for their highly credible associations with CRC risk and 59 variants at 49 loci that were classified as 'less-credible positive' SNPs; 72.2% of the 'positive' SNPs were successfully replicated in three large GWASs and the ones that were not replicated were downgraded to 'less-credible' positive (reducing the 'positive' variants to 14 at 11 loci). For the remaining 231 variants, which were previously reported, our meta-analyses found no evidence to support their associations with CRC risk., Conclusion: The CRCgene2 database provides an updated list of genetic variants related to CRC risk by using harmonised methods to assess their credibility., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY. Published by BMJ.)

Background: There is a clear need for systematic appraisal of models/factors predicting colorectal cancer (CRC) metastasis and recurrence because clinical decisions about adjuvant treatment are taken on the basis of such variables., Methods: We conducted an umbrella review of all systematic reviews of observational studies (with/without meta-analysis) that evaluated risk factors of CRC metastasis and recurrence. We also generated an updated synthesis of risk prediction models for CRC metastasis and recurrence. We cross-assessed individual risk factors and risk prediction models., Results: Thirty-four risk factors for CRC metastasis and 17 for recurrence were investigated. Twelve of 34 and 4/17 risk factors with p < 0.05 were estimated to change the odds of the outcome at least 3-fold. Only one risk factor (vascular invasion for lymph node metastasis [LNM] in pT1 CRC) presented convincing evidence. We identified 24 CRC risk prediction models. Across 12 metastasis models, six out of 27 unique predictors were assessed in the umbrella review and four of them changed the odds of the outcome at least 3-fold. Across 12 recurrence models, five out of 25 unique predictors were assessed in the umbrella review and only one changed the odds of the outcome at least 3-fold., Conclusions: This study provides an in-depth evaluation and cross-assessment of 51 risk factors and 24 prediction models. Our findings suggest that a minority of influential risk factors are employed in prediction models, which indicates the need for a more rigorous and systematic model construction process following evidence-based methods.

Background: Despite a burgeoning literature during the last two decades regarding perioperative risk management of anal fistula, little is known about its risk factors that influence postoperative recurrence. We performed a meta-analysis to summarize and assess the credibility of evidence of potential risk factors for anal fistula recurrence (AFR) after surgery., Methods: Pubmed and EMBASE without language restriction were searched from inception to April 2018 that reported risk factors which predisposed recurrence after anal fistula surgery. We excluded studies that involved patients with anal fistula associated with Crohn's disease. MOOSE guidelines were followed when this meta-analysis was performed. We used random-effects models to pool relative risks (RRs) with 95% confidence intervals (CIs). Evidence from observational studies was graded into high-quality (Class I), moderate-quality (Class II/III) and low-quality (Class IV) based on Egger's P value, total sample size and between-study heterogeneity., Results: Of 3514 citations screened, 20 unique observational studies comprising 6168 patients were involved in data synthesis. High-quality evidence showed that AFR was associated with high transsphincteric fistula (RR, 4.77; 95% CI, 3.83 to 5.95), internal opening unidentified (RR, 8.54; 95% CI, 5.29 to 13.80), and horseshoe extensions (RR, 1.92; 95% CI, 1.43 to 2.59). Moderate-quality evidence suggested an association with prior anal surgery (RR, 1.52; 95% CI, 1.04 to 2.23), seton placement surgery (RR, 2.97; 95% CI, 1.10 to 8.06), and multiple fistula tract (RR, 4.77; 95% CI, 1.46 to 15.51). High-quality evidence demonstrated no significant association with gender or smoking; moderate-quality evidence also suggested no association with age, tertiary referral, alcohol use, diabetes mellitus, obesity, preoperative seton drainage, high internal opening, postoperative drainage, mucosal advancement flap surgery, supralevator extensions, location or type of anal fistula., Conclusion: Several patient, surgery and fistula-related factors are significantly associated with postoperative AFR. These findings strengthen clinical awareness of early warning to identify patients with high-risk disease recurrence for AFR., (Copyright © 2019 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.)

Prediction models allow accurate estimate of individualized prognosis. Increasing numbers of models on survival of CRC patients with surgical resection are being published. However, their performance and potential clinical utility have been unclear. A systematic search in MEDLINE and Embase databases (until 9th April 2018) was performed. Original model development studies and external validation studies predicting any survival outcomes from CRC (follow-up ≥1 year after surgery) were included. We conducted random-effects meta-analyses in external validation studies to estimate the performance of each model. A total of 83 original prediction models and 52 separate external validation studies were identified. We identified five models (Basingstoke score, Fong score, Nordinger score, Peritoneal Surface Disease Severity Score and Valentini nomogram) that were validated in at least two external datasets with a median summarized C-statistic of 0.67 (range: 0.57-0.74). These models can potentially assist clinical decision-making. Besides developing new models, future research should also focus on validating existing prediction models and investigating their real-word impact and cost-effectiveness for CRC prognosis in clinical practice., (Copyright © 2019 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: It remains unclear whether or not preservation of the left colic artery (LCA) for colorectal cancer surgery. The objective of this updated systematic review and meta-analysis is to evaluate the current scientific evidence of LCA non-preservation versus LCA preservation in colorectal cancer surgery., Methods: A systematic search was conducted in the Medline, Embase, PubMed, Cochrane Library, ClinicalTrials, Web of Science, China National Knowledge Infrastructure and Chinese BioMedical Literature Database, and reference without limits. Quality of studies was evaluated by using the Newcastle-Ottawa scale and the Cochrane Collaboration's tool for assessing the risk of bias. Effective sizes were pooled under a random- or fixed-effects model. The funnel plot was used to assess the publication bias. The outcomes of interest were oncologic consideration including the number of apical lymph nodes, overall recurrence, 5-years overall survival, and 5-years disease-free survival (DFS); safety consideration including overall 30-day postoperative morbidity and overall 30-day postoperative mortality; anatomic consideration including anastomotic circulation, anastomotic leakage, urogenital, and defaecatory dysfunction., Results: Twenty-four studies including 4 randomized controlled trials (RCTs) and 20 cohort studies with a total of 8456 patients (4058 patients underwent LCA non-preservation surgery vs 4398 patients underwent LCA preservation surgery) were enrolled in this meta-analysis. The preservation of LCA was associated with significantly less anastomotic leakage (odds ratio 1.23, 95% confidence interval 1.02-1.48, P = .03). In term of sexual dysfunction, urinary retention, the number of apical lymph nodes, and long-term oncologic outcomes, there were no significant differences between the LCA non-preservation and LCA preservation group. It was hard to draw definitive conclusions on other outcomes including operation time, blood loss, the first postoperative exhaust time, and perioperative morbidity and mortality for insufficient data and highly significant heterogeneity among studies., Conclusions: The pooled data provided evidence to support the LCA preservation preferred over LCA non-preservation in anastomotic leakage. Future more large-volume, well-designed RCTs with extensive follow-up are needed to draw a definitive conclusion on this dilemma.

Current opinion varies in the roles of the IL-10 polymorphisms in the process of hepatitis B virus (HBV) infection. We have performed a systemic review and up-dated meta-analysis including 37 eligible case-control studies to summarize all the available data on the association between IL-10 polymorphisms and development of HBV infection. In the present study, we found that the IL-10-1082 G/A, -592 C/A polymorphisms were associated with a significantly decreased risk of chronic HBV infection (AA + GA vs. GG: P = 0.003, OR = 0.55, 95% CI = 0.37-0.82; AA vs. CA + CC: P = 0.03, OR = 0.83, 95% CI = 0.71-0.98). While the -819 C/T TT carriers were associated with a borderline significantly decreased risk of chronic HBV infection (TT vs. CT + CC: P = 0.05, OR = 0.82, 95% CI = 0.68-1.00). Significant result was observed in the association between IL-10-1082 G/A polymorphism and HBV clearance (AA vs. GG: P = 0.04, OR = 1.33, 95% CI = 1.01-1.75). In addition, significant association was found between the -1082 G/A, -819 C/T polymorphisms and an increased risk of progression of HBV infection from asymptomatic carrier to chronic hepatitis B (AA + GA vs. GG: P = 0.0003, OR = 2.13, 95% CI = 1.41-3.22; TT + CT vs. CC: P = 0.005, OR = 1.53, 95% CI = 1.13-2.07), whereas the -592 C/A polymorphism was associated with a significantly decreased risk of progression from asymptomatic carrier to hepatocellular carcinoma (AA vs. CC: P = 0.02, OR = 0.63, 95% CI = 0.43-0.92). Our meta-analysis suggested that the IL-10 polymorphisms might be associated with a decreased risk of chronic HBV infection, while the -1082 AA carriers might be more likely to clear HBV following acute infection. In addition, these three polymorphisms might cast in roles of the progression of HBV infection.

Background: The role of the tumor necrosis factor-α (TNF-α) G-308A polymorphism in the risk of ischemic heart disease (IHD) has been controversial in recent decades. A substantial number of newly-published studies concerning the association between the TNF-α polymorphism and IHD risk have emerged after the publication of the latest meta-analysis. Therefore, we conducted an updated meta-analysis to further investigate the influence of this polymorphism on IHD., Methods: Electronic databases (PubMed, Embase, CNKI, and Wanfang) were systematically searched to identify all relevant papers published before September 25(th), 2014. The quality of all eligible studies was assessed. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) of all studies and high-quality studies were assessed by the fixed/random-effects model in Review Manager 5.0.25 and STATA 10.0. Heterogeneity and publication bias were detected; sensitivity analysis was conducted., Results: Data from 36 studies were recorded after study selection and exclusion. Under the dominant model, the results of pooled analysis of high-quality studies suggested that the G-308A polymorphism was associated with an increased risk of IHD in total population (P = 0.02, OR = 1.13, 95% CI = 1.02-1.24, P heterogeneity = 0.009, I(2) = 45%). No significant result was obtained in Asians, Caucasians, or Indians., Conclusion: The TNF-α -308A allele is probably associated with an increased risk of IHD in total population, but to further identify this association, more high quality studies in Indians and Africans are merited.