Computing lifetime incidence of esophageal adenocarcinoma and age-specific prevalence of Barrett's esophagus.

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Alcohol Drinking and the Risk of Barrett's Esophagus and Esophageal Adenocarcinoma

Background Barrett’s esophagus is the precursor to esophageal adenocarcinoma (EAC). EAC detected from endoscopic surveillance programs accounts for <10% of all EAC, suggesting a large number of patients with Barrett’s esophagus are likely unaccounted for. Several studies have estimated the observed prevalence of Barrett’s esophagus to be approximately 1%, but this may be an underestimate. The aim of this study is to use population incidence of EAC and rate of progression from Barrett’s esophagus from large cohort studies to estimate a realistic prevalence of Barrett’s esophagus. Methods A simple tree cohort model was created for progression to EAC from birth to death (100 years) for American and Australian population. Lifetime risk of esophageal cancer and adenocarcinoma were endpoints. This was then used to back-calculate age-specific and overall prevalence of Barrett’s esophagus using an optimisation algorithm. Results Lifetime risk of esophageal cancer and adenocarcinoma in US Whites is 0.56% and 0.36% respectively, while in Australian population is slightly higher at 0.81% and 0.61% (range 0.57% - 0.65%). Estimated overall prevalence of Barrett’s esophagus is ~3% (±0.3%) and ~5.4% (±0.6%) in US White and Australian populations, while in males is 5.3% (±0.6%) and 7.4% (±0.3%), respectively. Female cohorts were seen to have lower chance of developing esophageal cancer, adenocarcinoma, and Barrett’s esophagus. Conclusion Cohort studies of Barrett’s esophagus are likely to underestimate its prevalence of this silent disease. Computational models based on progression from Barrett’s esophagus to EAC accounting for undetected disease reveal higher estimates, which can help in future screening options.

Screening and surveillance for Barrett esophagus.

Cost-Effectiveness of Endoscopic Screening Followed by Surveillance for Barrett's Esophagus: A Review

Adipose deposition and Barrett’s esophagus: Is all fat created equal?

To investigate individual susceptibility to gastroesophageal reflux disease, Barrett esophagus, and esophageal adenocarcinoma, the authors studied the frequency of the common G870A polymorphism of CCND1, which encodes cyclin D1, a key cell cycle regulatory protein. The study population included 307 patients who were enrolled in a prospective case-control study to evaluate lifestyle risk factors and molecular alterations in gastroesophageal reflux disease (n = 126 patients), Barrett esophagus (n = 125 patients), and esophageal adenocarcinoma (n = 56 patients). A control group included 95 strictly asymptomatic individuals. Genomic DNA was extracted from cases and controls, and polymerase chain reaction was used to amplify exon 4 of CCND1. After digestion with BsrI, acrylamide gel electrophoresis was used to identify the wild type and common G870A polymorphic alleles. The frequency of alleles (G/G, G/A, A/A) was compared between cases and controls. Immunohistochemistry was used to study cyclin D1 distribution in among patients in the case group. Compared with the asymptomatic control group, and adjusted for age and gender, increasing frequencies were seen for the A/A genotype in patients with gastroesophageal reflux disease (odds ratio [OR], 2.83; 95% confidence interval [95% CI], 1.09-7.34), Barrett esophagus (OR, 3.69; 95% CI, 1.46-9.29), and esophageal adenocarcinoma (OR, 5.99; 95% CI, 1.86-18.96). No association was seen between genotype and cyclin D1 overexpression. The CCND1 A/A genotype was associated with increased risk for gastroesophageal reflux disease, Barrett esophagus, and esophageal adenocarcinoma. The contribution of this polymorphism to susceptibility of defined stages of progression to esophageal adenocarcinoma suggested potential application in endoscopic Barrett surveillance programs.

Objective. To investigate the relationship between use of asthma medication and nitrates and risk of reflux oesophagitis, Barrett's oesophagus and oesophageal adenocarcinoma. Material and methods. Data were collected on use of asthma medication and nitrates at least 1 year before interview from patients with reflux oesophagitis, Barrett's oesophagus and oesophageal adenocarcinoma. Associations between use of asthma medications and nitrates and the risk of reflux oesophagitis, Barrett's oesophagus and oesophageal adenocarcinoma were estimated using multiple logistic regression. Results. Nine hundred and forty-one subjects were recruited: 230 reflux oesophagitis, 224 Barrett's oesophagus, 227 oesophageal adenocarcinoma patients and 260 population controls. Barrett's oesophagus patients were more likely than controls to have had a diagnosis of asthma (odds ratio 2.15, 95% confidence interval 1.15–4.03) and to have used asthma medications (odds ratio 2.13, 95% confidence interval 1.09–4.16). No significant associations were observed between use of asthma medication or nitrates and reflux oesophagitis or oesophageal adenocarcinoma. Conclusions. Gastro-oesophageal reflux symptoms appear to confound the association between asthma medication use and Barrett's oesophagus. However, it is possible that asthma medications may increase the risk of Barrett's oesophagus by other mechanisms.

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The skinny on obesity and reflux

American Gastroenterological Association Technical Review on the Management of Barrett's Esophagus

Incidence of esophageal adenocarcinoma (EA) has risen substantially in Western countries over recent decades. Established risk factors for EA and its precursor lesion, Barrett’s esophagus (BE), include reflux, obesity, and tobacco smoking. Inherited genetic variation also influences disease risk, although only a limited number of susceptibility loci have been identified. Genomic analyses of EA tumors have revealed a distinctive mutational signature, high mutational burden, and extensive somatic chromosome alterations, features also observed in high-risk BE tissue. To explore whether germline variation in DNA repair-related genes may be associated with altered disease susceptibility, we analyzed data from a recent meta-analysis of genome-wide association studies (GWAS) encompassing 4,112 EA cases, 6,167 BE cases, and 17,159 controls, representing the largest sample size assembled for these conditions. Using a gene-based testing approach (VEGAS2), we assessed 263 DNA repair-related genes and found that variation in NEIL2, a mediator of base excision repair (BER), was significantly associated with risk of BE (P=1.4×10-5, q<0.05). No other gene-level associations with BE or EA survived correction for multiple comparisons. SNP-level analysis of 239 polymorphisms at the NEIL2 locus revealed six variants strongly associated with altered risk of BE (P<5×10-5, q<0.01), with the index SNP classified as an intronic eQTL for NEIL2 in esophageal tissue. Four of these SNPs were also associated with risk of EA (P<0.05), with odds ratios in the same direction and of similar magnitude. Our results provide evidence that germline genetic variation in a DNA glycosylase enzyme (NEIL2) may influence risk of BE/EA, and suggest a potential novel biological role for altered BER in BE/EA pathogenesis. Citation Format: Matthew F. Buas, Li Yan, Xuan Peng, Qianya Qi, Jianhong Chen, Aaron Thrift, Qianchuan He, Lynn Onstad, Puya Gharahkhani, Stuart MacGregor, Thomas L. Vaughan, Margaret M. Madeleine. Germline variation in DNA repair genes and risk of Barrett's esophagus and esophageal adenocarcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1588.

Incidence rates for oesophageal adenocarcinoma have increased by over 500% during the past few decades without clear reasons. Gastro-oesophageal reflux disease, obesity and smoking have been identified as risk factors, although the demographic distribution of these risk factors is not consistent with the demographic distribution of oesophageal adenocarcinoma, which is substantially more common among whites and males than any other demographic groups. Numerous epidemiological studies have suggested associations between dietary factors and the risks of oesophageal adenocarcinoma and its precursor, Barrett's oesophagus, though a comprehensive review is lacking. The main aim of the present review is to consider the evidence linking dietary factors with the risks of oesophageal adenocarcinoma, Barrett's oesophagus, and the progression from Barrett's oesophagus to oesophageal adenocarcinoma. The existing epidemiological evidence is strongest for an inverse relationship between intake of vitamin C, β-carotene, fruits and vegetables, particularly raw fruits and vegetables and dark green, leafy and cruciferous vegetables, carbohydrates, fibre and Fe and the risk of oesophageal adenocarcinoma and Barrett's oesophagus. Patients at higher risk for Barrett's oesophagus and oesophageal adenocarcinoma may benefit from increasing their consumption of fruits and vegetables and reducing their intake of red meat and other processed food items. Further research is needed to evaluate the relationship between diet and the progression of Barrett's oesophagus to oesophageal adenocarcinoma. Evidence from cohort studies will help determine whether randomised chemoprevention trials are warranted for the primary prevention of Barrett's oesophagus or its progression to cancer.

The strong male predominance in Barrett's esophagus (BE) and esophageal adenocarcinoma (EAC) remains inadequately explained, but sex hormones might be involved. We hypothesized that single nucleotide polymorphisms (SNPs) in the androgen pathway influence risk of developing BE and EAC. This genetic-epidemiological analysis included 14 studies from Australia, Europe and North America. Polymorphisms in 16 genes coding for the androgen pathway were analyzed using a gene-based approach: versatile gene-based test association study. This method evaluates associations between a trait and all SNPs within a specific gene rather than each SNP marker individually as in a conventional GWAS. The data were stratified for sex, body-mass index, waist-to-hip ratio, tobacco smoking and gastroesophageal reflux status. Included were data from 1,508 EAC patients, 2,383 BE patients and 2,170 control participants. SNPs within the gene CYP17A1 were associated with risk of BE in the sexes combined (p = 0.002) and in males (p = 0.003), but not in females separately (p = 0.3). This association was found in tobacco smokers (p = 0.003) and in BE patients without reflux (p = 0.004), but not in nonsmokers (p = 0.2) or those with reflux (p = 0.036). SNPs within JMJD1C were associated with risk of EAC in females (p = 0.001). However, none of these associations replicated in a subsequent sample. Fourteen other genes studied did not reach statistically significant levels of association with BE, EAC or the combination of BE and EAC, after correcting for the number of genes included in the analysis. In conclusion, genetic variants in the androgen-related genes CYP17A1 and JMJD1C might be associated with risk of BE and EAC, respectively, but replication data with larger sample sizes are needed.

Association Between Length of Barrett's Esophagus and Risk of High-grade Dysplasia or Adenocarcinoma in Patients Without Dysplasia