Fish consumption and colorectal cancer risk in humans: a systematic review and meta-analysis

BackgroundFish consumption may protect against colorectal cancer, but results from observational studies are inconsistent; therefore, a systematic review with a meta-analysis was conducted.MethodsRelevant studies were identified by a search of MEDLINE and EMBASE databases to May 2011, with no restrictions. Reference lists from retrieved articles also were reviewed. Studies that reported odds ratio (OR) or relative risk estimates with 95% confidence intervals (CIs) for the association between the consumption of fish and the risk of colorectal, colon, or rectal cancer were included. Two authors independently extracted data and assessed study quality. The risk estimate (hazard ratio, relative risk, or OR) of the highest and lowest reported categories of fish intake were extracted from each study and analyzed using a random-effects model.ResultsTwenty-two prospective cohort and 19 case-control studies on fish consumption and colorectal cancer risk met the inclusion criteria and were included in the meta-analysis. Our analysis found that fish consumption decreased the risk of colorectal cancer by 12% (summary OR, 0.88; 95% CI, 0.80-0.95). The pooled ORs of colorectal cancer for the highest versus lowest fish consumption in case-control studies and cohort studies were 0.83 (95% CI, 0.72-0.95) and 0.93 (95% CI, 0.86-1.01), respectively. There was heterogeneity among case-control studies (P < .001) but not among cohort studies. A significant inverse association was found between fish intake and rectal cancer (summary OR, 0.79; 95% CI, 0.65-0.97), and there was a modest trend seen between fish consumption and colon cancer (summary OR, 0.96; 95% CI, 0.81-1.14). This study had no publication bias.ConclusionOur findings from this meta-analysis suggest that fish consumption is inversely associated with colorectal cancer.     

Association of type 2 diabetes mellitus and the risk of colorectal cancer: A meta-analysis and systematic review

AIM: To provide a quantitative assessment of the association between type 2 diabetes mellitus(T2DM)and the risk of colorectal cancer(CRC).METHODS: Systematic review was conducted thorough MEDLINE, EMBASE, Cochrane Library, andISI Web of knowledge databases till 31 st January 2014.This meta-analysis included the cohort studies that illustrated relative risk(RR) or odds ratio estimates with 95%CI for the predictive risk of CRC by T2 DM.Summary relative risks with 95%CI were analyzed by using an effects summary ratio model. Heterogeneity among studies was assessed by the Cochran's Q and I 2statistics.RESULTS: The meta analysis of 8 finally selected studies showed a positive correlation of T2 DM with the risk of CRC as depicted by effects summary RR of 1.21(95%CI: 1.02-1.42). Diabetic women showed greater risk of developing CRC as their effect summary RR of 1.22(95%CI: 1.01-49) with significant overall Z test at 5% level of significance was higher than the effect summary RR of 1.17(95%CI: 1.00-1.37) of men showing insignificant Z test. The effect summary RR of 1.19 with 95%CI of 1.07-1.33 indicate a positive relationship between DM and increased risk of CRC with significant heterogeneity(I 2 = 92% and P-value 0.05).CONCLUSION: Results from this systematic review and meta-analysis report that diabetic people have an increased risk of CRC as compared to non-diabetics.     

Primary biliary cirrhosis and cancer risk: A systematic review and meta-analysis

Several studies have indicated that primary biliary cirrhosis (PBC) may be associated with increased risk of some cancers, but the results are controversial. We conducted a systematic review of studies to examine the association of PBC with cancer risk by meta-analysis. We searched the PubMed and EMBASE databases for English-language studies published before November 2011. Studies were included if they reported relative risk estimates with 95% confidence intervals (CIs) or related data for the association between PBC and cancer risk. Approximately 16,300 PBC patients from several countries were included in this analysis. Of the 3510 titles identified, 16 publications involving 17 studies meeting the inclusion criteria were included in the meta-analysis. Compared with the general population, PBC patients had a significantly higher risk of overall cancer (pooled rate ratio [RR], 1.55; 95% CI, 1.28-1.83) and hepatocellular carcinoma (HCC) (pooled RR, 18.80; 95% CI, 10.81-26.79). For stomach and pancreas cancers, the results of one study that only examined male patients with PBC indicated that PBC patients had increased risk of stomach cancer and pancreatic cancer, whereas the results of other studies of mixed-sex patients showed no significant association. Therefore, despite inconsistent results, the meta-analysis could not be conducted for assessing the association. PBC was not significantly associated with increased risk of other cancers. Conclusion: The present systematic review and meta-analysis demonstrate that PBC is closely associated with a greater risk of overall cancer and HCC, but not with other cancers. The data regarding the association between PBC and risks of several cancers need to be further confirmed in future studies. (HEPATOLOGY 2012).     

Statins and the risk of colorectal cancer: An updated systematic review and meta-analysis of 40 studies

AIM:To investigate the association between statin use and colorectal cancer risk,we conducted an updated meta-analysis of published studies.METHODS:We performed a comprehensive search for studies published up to July 2013.Eligible studies for this meta-analysis were either randomized controlled trials(RCTs)or observational studies(casecontrol or cohort)evaluating any exposure to statins and the risk of colorectal cancer.Two reviewers selected studies based on predefined inclusion criteria,and abstracted the data.Pooled relative risk(RR)estimates with their 95%CI were calculated using fixedand random-effects models.Then,we assessed the potential presence of publication bias and betweenstudies heterogeneity.To evaluate the results,we also performed a"leave-one-out"sensitivity analysis.RESULTS:A total of 40 studies,involving more than eight million subjects,contributed to the analysis.They were grouped on the basis of study design and,consequently,three separate meta-analyses were conducted.A similar modest reduction in the risk of colorectal cancer with statin use was observed,which was not statistically significant among RCTs(RR=0.89,95%CI:0.74-1.07;n=8),but reached statistical significance among cohort studies(RR=0.91,95%CI:0.83-1.00;n=13)and case-control studies(RR=0.92,95%CI:0.87-0.98;n=19).While we did not find significant evidence of selective outcome reporting or publication bias,substantial heterogeneity was detected,mainly among the observational studies.The sensitivity analysis confirmed the stability of our results.CONCLUSION:A modest reduction in risk of colorectal cancer among statin users cannot be disproved.Further targeted research is warranted.2014 Baishideng Publishing Group Co.,Limited.All rights     

Effect of Quxie capsule in patients with colorectal cancer: A systematic review and meta-analysis

Objective:To investigate whether the Quxie capsule can decrease relapse, metastasis, and symptoms, as well as alleviate the side effects in colorectal cancer (CRC) patients.Methods:A comprehensive literature search of multiple databases was performed. Two reviewers independently selected trials that assessed the relapse-metastasis rate, degree of symptoms, and side effects of Quxie capsule for CRC. The meta-analysis was performed using Review Manager 5.3.Results:This meta-analysis included 6 studies, with a total of 408 cases. The quality of the included studies was generally low, with only 1 trial of high quality. A statistically significant difference was observed in the relapse-metastasis rate between the Quxie capsule and control groups after 2-years follow-up (n = 185, relative risk (RR) = 0.13, 95% confidence interval (CI) 0.04–0.46; P = .002). The Quxie capsule was found to reduce the traditional Chinese medicine symptom score as compared to the control (n = 208, weighted mean differences (WMD) = −4.15, 95% CI −7.30 to −1.00; P = .010), while it showed no significant improvement in the Karnofsky Performance Status score (n = 138, WMD = 5.05; 95% CI −2.95 to 13.04; P = .22). There was no difference in adverse events between the 2 groups (P = .66).Conclusion:This systematic review and meta-analysis showed no clear superiority of Quxie capsule for CRC patients receiving chemotherapy. The effect of Quxie capsule in CRC patients should be examined by high quality, large sample size, multi-center RCTs, with longer follow-up.     

Association of 8q24.21 loci with the risk of colorectal cancer: a systematic review and meta-analysis

Background and Aim: Recent genome‐wide association studies of colorectal cancer (CRC) have identified rs6983267 and trs10505477 polymorphisms as key loci in the 8q24 region to be associated with CRC. In the present study, we performed a meta‐analysis to determine whether these loci are risk factors for susceptibility to CRC. Methods: We meta‐analyzed the 22 included studies (47 003 cases and 45 754 controls) that evaluated the association of rs6983267 and trs10505477 with CRC under alternative genetic models. Results: A meta‐analysis of the pooled data showed allelic and genotypic association of the rs6983267 polymorphism with CRC risk in Asians, Europeans, and European‐Americans. A subanalysis of the US studies showed negative results in the studies with non‐identified ethnicity of the patients. A meta‐analysis of included studies of rs10505477 polymorphisms identified allelic and genotypic associations with CRC risk in the US patients. A further meta‐analysis of the US studies demonstrated positive results in the studies with non‐identified ethnicity of the samples. Conclusion: Our data suggested that the rs6983267 G > T polymorphism is a risk factor for CRC in Asians, Europeans, and Americans with European ancestry.     

二甲双胍与结直肠腺瘤患病风险相关性的荟萃分析

目的探索糖尿病患者服用二甲双胍是否可降低患结肠直肠腺瘤的风险。 方法从PubMed、Elsevier-ScienceDirect、万方、维普数据库中检索建库以来至2017年7月所有关于2型糖尿病患者使用二甲双胍与患结直肠腺瘤风险相关性的研究。按照纳入及排除标准选择入选。 结果共计纳入9项研究,其中实验组4 256例,对照组17 206例,结果显示,服用二甲双胍者较未服用二甲双胍者患结直肠腺瘤风险降低（OR=0.83,95%CI：0.72~0.95;P=0.008）,差异具有统计学意义。 结论二甲双胍的使用可能与结肠直肠腺瘤的风险降低有关。     

Body mass index and colorectal cancer prognosis: a systematic review and meta-analysis

Colorectal cancer is one of the most common cancers worldwide. However, it is unclear what influence body mass index (BMI) has on colorectal cancer prognosis. We conducted a systematic review and meta-analysis of observational studies to examine the association of BMI with colorectal cancer outcomes. We searched MEDLINE and EMBASE databases from inception to February 2015 and references of identified articles. We selected observational studies that reported all-cause mortality, colorectal cancer-specific mortality, recurrence and disease-free survival according to BMI category. Random-effects meta-analyses were conducted to combine estimates. We included 18 observational studies. Obese patients had an increased risk of all-cause mortality [relative risk (RR) 1.14; 95 % confidence interval (CI) 1.07–1.21], cancer-specific mortality (RR 1.14; 95 % CI 1.05–1.24), recurrence (RR 1.07; 95 % CI 1.02–1.13) and worse disease-free survival (RR 1.07; 95 % CI 1.01–1.13). Underweight patients also had an increased risk of all-cause mortality (RR 1.43; 95 % CI 1.26–1.62), cancer-specific mortality (RR 1.50; 95 % CI 1.20–1.87), recurrence (RR 1.13; 95 % CI 1.05–1.21) and worse disease-free survival (RR 1.27; 95 % CI 1.13–1.43). Overweight patients had no increased risk for any of the outcomes studied. Both obese and underweight patients with colorectal cancer have an increased risk of all-cause mortality, cancer-specific mortality, disease recurrence and worse disease-free survival compared to normal weight patients.     

Vitamin D receptor gene polymorphisms and colorectal cancer risk: a systematic meta-analysis

AIM:To investigate the relationship between polymorphisms present in the vitamin D receptor(VDR) gene and colorectal cancer risk,a systematic meta-analysis of population-based studies was performed.METHODS:A total of 38 relevant reports published between January 1990 and August 2010 were identified,of which only 23 qualified for this meta-analysis based on our selection criteria.Five polymorphic variants of the VDR gene,including Cdx-2(intron 1e) and FokI(exon 2) present in the 5' region of the gene,and BsmI(intron 8),ApaI(intron 8),and TaqI(exon 9) sites present in the 3' untranslated region(UTR),were evaluated for possible associations with colorectalcancer risk.Review manager 4.2 was used to perform statistical analyses.RESULTS:In the meta-analysis performed,only the BsmI polymorphism was found to be associated with colorectal cancer risk.In particular,the BsmI B genotype was found to be related to an overall decrease in the risk for colorectal cancer [BB vs bb:odds ratio(OR) = 0.87,95% CI:0.80-0.94,P = 3 × 10-4;BB vs Bb + bb:OR = 0.90,95% CI:0.84-0.97,P = 5 × 10-4].Moreover,in subgroup analyses,the BsmI B genotype was significantly associated with colon cancer,and not rectal cancer.An absence of between-study heterogeneity was also observed.CONCLUSION:A meta-analysis of 23 published studies identified the BsmI polymorphism of the VDR gene to be associated with an increased risk of colon cancer.     

Angiotensin converting enzyme inhibitors and risk of lung cancer: A systematic review and meta-analysis

Background:We performed a meta-analysis to determine whether a consistent relationship exists between the use of angiotensin converting enzyme inhibitors (ACEIs) and the risk of lung cancer. Accordingly, we summarized and reviewed previously published quantitative studies.Methods:Eligible studies with reference lists published before June 1st, 2019 were obtained from searching several databases. Random effects’ models were used to summarize the overall estimate of the multivariate adjusted odds ratios (ORs) with 95% confidence intervals (CIs)Results:Thirteen observational studies involving 458,686 ACEI users were included in the analysis, Overall, pooled risk ratios indicate that ACEIs use was not a risk factor for lung cancer (RR 0.982, 95% C.I. 0.873 – 1.104; P = .76). There was significant heterogeneity between the studies (Q = 52.54; P < .001; I2 = 86.07). There was no significant association between ACEIs use and lung cancer in studies with over five years of ACEIs exposure (RR 0.95, 95% C.I. 0.75 – 1.20; P = .70); and ≤ 5years of exposure to ACEIs (RR 0.98, 95% C.I. 0.83 – 1.15; P = .77). There were no statistically significant differences in the pooled risk ratio obtained according to the study design (Q = 0.65; P = .723) and the comparator regimen (Q = 3.37; P = .19).Conclusions:The use of ACEIs was not associated with an increased risk of lung cancer. Nevertheless, well-designed observational studies with different ethnic populations are still needed to evaluate the long-term (over 10 years) association between ACEIs use and lung cancer.     

Association between oral contraceptive use and pancreatic cancer risk: A systematic review and meta-analysis

BACKGROUNDStudies on the association of oral contraceptive (OC) use and pancreatic cancer showed inconsistent findings. AIMTo evaluate the relationship between OC use and pancreatic cancer risk. METHODSA literature search for observational studies (case-control and cohort studies) was conducted up to December 2020. A meta-analysis was performed by calculating pooled relative risks (RRs) and 95% confidence intervals (CIs). Heterogeneity was assessed using Cochran’s chi-square test and I² statistic. Subgroup analyses were performed by study design, source of controls in case-control studies, number of cases of pancreatic cancers, study quality according to Newcastle-Ottawa Scale score, geographical region and menopausal status. All analyses were performed using Review Manager 5.3 (RevMan 5.3).RESULTSA total of 21 studies (10 case-control studies and 11 cohort studies) were finally included in the present meta-analysis, comprising 7700 cases of pancreatic cancer in total. A significant association was observed between the ever use of OC and pancreatic cancer risk in the overall analysis (RR = 0.85; 95%CI = 0.73-0.98; P = 0.03). Duration of OC use (< 1 year, < 5 years, 5-10 years, > 10 years) was not significantly associated with the risk of pancreatic cancer. Subgroup analyses revealed a statistically significant subgroup difference for the geographic region in which the study was conducted (Europe vs Americas vs Asia; P = 0.07). Subgroup analyses showed a statistically significant decrease in pancreatic cancer risk and OC use in high-quality studies, studies conducted in Europe, and in postmenopausal women. CONCLUSIONDespite the suggested protective effects of OC use in this meta-analysis, further epidemiological studies are warranted to fully elucidate the association between the use of OC and pancreatic cancer risk.     

Serum insulin level,HOMA-IR and prostate cancer risk: A systematic review and meta-analysis

AimsThis meta-analysis study was performed to assess serum insulin level and insulin resistance status in prostate cancer patients in observational studies.Materials and methodsA systematic literature search was performed for observational studies in Scopus, PubMed, Ovid and ISI Web of Science up to July 2017.ResultsFrom 2070 publication were searched firstly, only 10 studies with 9 and 6 arms included for the meta-analysis assessing serum insulin level and HOMA-IR status in prostate cancer patients, respectively. Pooled effects analysis showed that the Fasting insulin level was significantly higher in men with prostate cancer compared to control group (WMD = 2.12 μ IU/ml, 95%CI; 0.26, 3.99; P = 0.02). Sub-group analysis showed that the elevation in serum insulin level takes place only in patients with ages more than 65 years old (WMD = 3.88 μ IU/ml, 95%CI; 2.28, 5.48; P < 0.001). HOMA-IR was no significantly different between study groups. However, the difference got statistically significant after sub-grouping patients based on their age (WMD = 1.37, 95% CI; 0.61, 2.12; P < 0.001).ConclusionIn conclusion, the results of this meta-analysis study showed higher fasting serum insulin and HOMA-IR levels especially in patients with ages more than 65 years..     

Fasting blood glucose and risk of prostate cancer: A systematic review and meta-analysis of dose-response

Aim

This study aimed to test the dose-response relationship between fasting blood glucose (FBG) levels and risk of prostate cancer.

Nomograms for colorectal cancer:A systematic review

AIM: To assist in the selection of suitable nomograms for obtaining desired predictions in daily clinicalpractice.METHODS: We conducted electronic searches for journal articles on colorectal cancer(CRC)-associated nomograms using the search terms colon/rectal/colorectal/nomogram. Of 174 articles initially found, we retrieved 28 studies in which a nomogram for CRC was developed.RESULTS: We discuss the currently available CRCassociated nomograms, including those that predict the oncological prognosis, the short-term outcome of treatments, such as surgery or neoadjuvant chemoradiotherapy, and the future development of CRC. Developing nomograms always presents a dilemma. On the one hand, the desire to cover as wide a patient range as possible tends to produce nomograms that are too complex and yet have C-indexes that are not sufficiently high. Conversely, confining the target patients might impair the clinical applicability of constructed nomograms.CONCLUSION: The information provided in this review should be of use in selecting a nomogram suitable for obtaining desired predictions in daily clinical practice.     

A meta-analysis and systematic review of HIV risk behavior among fishermen

With HIV prevalence levels up to 30%, fishermen as a group have a comparable prevalence to at-risk populations such as female sex workers (FSWs), truck drivers, military personnel, and prisoners. This study examines sexual risk behavior among fishermen, primarily in Africa and Asia. A meta-analysis embedded within a systematic review is utilized for this study. This study included 44 peer-reviewed articles and gray literature from 1992 to 2012. The study found that 42% of fishermen engaged in transactional sex, 48% of whom reported not using a condom with FSWs. Ninety percent of the fishermen reported having partners outside of their regular partner, but only 7% reported using a condom with their regular partner. Mobility, peer norms, and alcohol were found to be contextual risks for HIV infection. The findings have important implications for HIV prevention, targeting fishermen, and their sexual networks. Prevention strategies are needed to address HIV risk among this population.