Risk factors and chemoprevention in Barrett's esophagus--an update

Dietary Intake in Relation to the Risk of Reflux Disease: A Systematic Review

Gastroesophageal reflux disease (GERD) is a chronic condition which has a high global prevalence. Dietary intake is considered to be a contributing factor for GERD. However, scientific evidence about the effect of diet on the risk of GERD is controversial. This systematic review was conducted to address this issue. A comprehensive structured search was performed using the MEDLINE, Scopus, and Web of Science databases up to August 2020, in accordance with the PRISMA statement. No restrictions were set in terms of language, time of publication, or study location. Study selection and data abstraction was conducted independently by two authors, and risk of bias was assessed using a modified Quality in Prognosis Studies Tool. Eligible studies evaluating the impact of food and dietary pattern on GERD were included in qualitative data synthesis. After excluding duplicate, irrelevant, and low quality studies, 25 studies were identified for inclusion: 5 case-control studies, 14 cross-sectional studies, and 6 prospective studies. This review indicates that high-fat diets, carbonated beverages, citrus products, and spicy, salty, and fried foods are associated with risk of GERD.

Esophageal Columnar Metaplasia in Childhood: A Population-Based Case Series Analysis

BACKGROUND

Adults with Barrett's esophagus (BE) are often entered into surveillance for esophageal adenocarcinoma (EAC), although cancer risk is relatively low. BE can be detected in children (< 16 years). Little is known about the epidemiology of pediatric BE, and it is unclear what the optimal surveillance regimes are in children.

AIM

To evaluate the demographic and clinical characteristics, and future neoplastic progression risk in all pediatric BE patients diagnosed in Northern Ireland between 1993 and 2010.

METHODS

Data from the population-based Northern Ireland BE register were matched to the Northern Ireland Cancer Registry for EAC outcomes until end 2013. Age-adjusted incidence of pediatric BE was calculated, and characteristics between pediatric and adult BE patients compared using Chi-square tests.

RESULTS

Over 18 years, 42 pediatric BE patients (< 16 years) were identified, equivalent to an age-adjusted incidence of < 2 per 100,000 children. There was a clear age differential, with BE incidence increasing with age within the pediatric population. The majority (85.7%) of patients were male, a significantly higher male/female ratio than adult BE patients (p < 0.001). No pediatric BE patients progressed to high-grade dysplasia (HGD) or EAC, although the eldest patient was aged 34 years by the end of follow-up.

CONCLUSIONS

This is the largest series of pediatric BE ever reported. It demonstrates that pediatric BE is rare. The male preponderance of this condition is more apparent in childhood compared with adult cases. No children developed HGD/EAC during follow-up, suggesting that regular surveillance is not required, at least until adulthood.

Protective Propensity of Race or Environmental Features in the Development of Barrett's Esophagus in African Americans - A Single Center Pilot Study

BACKGROUND AND STUDY AIMS

Barrett's Esophagus (BE) is a well-recognized pre-malignant condition. Previous data indicate histologically confirmed BE frequency varies by ethnicity in the United States. However, clinical factor assessment to explain this has only occurred in a veteran population to date. The study aim was to determine which clinical factors may be associated with the ethnic variation seen in histologically confirmed BE among a general population.

PATIENTS AND METHODS

The University of Florida-Jacksonville endoscopy database was searched for all cases of endoscopic BE from September 2002 to October 2012. Histologic BE was diagnosed only if salmon colored, columnar-appearing esophageal mucosa was seen at endoscopy and biopsy revealed intestinal metaplasia with Alcian blue-stained goblet cells. Data collected included: age/BMI at diagnosis, ethnicity, sex, GERD history, atypical manifestations, endoscopic BE length, presence of esophageal stricture/ulcer/hiatal hernia, presence/absence of dysplasia and medication use (aspirin/NSAIDs/statin/PPI).

RESULTS

Salmon colored esophageal mucosa was observed in 1105 of 15,564 patients (7.1%) with BE histologically confirmed in 249 of 1105 patients (23%). Ethnic distribution of histologic BE patients: 83% non-Hispanic white (nHw), 13% African American (AA) and 4% other. No difference was seen between groups with regard to BMI, GERD symptom/complications, BE length, and cigarette, alcohol or medication use.

CONCLUSION

BE occurs primarily in nHw in north Florida. This occurs despite similarities in GERD history, cigarette/alcohol use, medications prescribed and BMI. Molecular level investigation is necessary to explain this observed disparity between nHw and AA.

Barrett’s oesophagus: Current controversies

Oesophageal adenocarcinoma is rapidly increasing in Western countries. This tumour frequently presents late in its course with metastatic disease and has a very poor prognosis. Barrett’s oesophagus is an acquired condition whereby the native squamous mucosa of the lower oesophagus is replaced by columnar epithelium following prolonged gastro-oesophageal reflux and is the recognised precursor lesion for oesophageal adenocarcinoma. There are multiple national and society guidelines regarding screening, surveillance and management of Barrett’s oesophagus, however all are limited regarding a clear evidence base for a well-demonstrated benefit and cost-effectiveness of surveillance, and robust risk stratification for patients to best use resources. Currently the accepted risk factors upon which surveillance intervals and interventions are based are Barrett’s segment length and histological interpretation of the systematic biopsies. Further patient risk factors including other demographic features, smoking, gender, obesity, ethnicity, patient age, biomarkers and endoscopic adjuncts remain under consideration and are discussed in full. Recent evidence has been published to support earlier endoscopic intervention by means of ablation of the metaplastic Barrett’s segment when the earliest signs of dysplasia are detected. Further work should concentrate on establishing better risk stratification and primary and secondary preventative strategies to reduce the risk of adenocarcinoma of the oesophagus.

Risk of histologic Barrett's esophagus between African Americans and non-Hispanic whites: A meta-analysis

Background

Barrett's esophagus (BE) is rare in African Americans (AA). However, the risk difference magnitude in histologic BE prevalence between AA and non-Hispanic whites (nHw) has not been quantified to date.

Objective

The objective of this article is to determine the degree of histologic BE risk difference between AA and nHw.

Methods

PubMed, Web of Science and EMBASE were searched for studies reporting histologic BE in AA/nHw for inclusion. Pooled odds ratios (ORs) with risk estimates of histologic BE occurrence between AA/nHw were calculated along with 95% confidence intervals (CIs). Forest plots were used to quantify heterogeneity. Funnel plots and the Cochrane Collaboration Risk of Bias tool were used to assess bias risk.

Results

Eight studies reported BE histologic confirmation in AA/nHw. Analysis demonstrated a nearly 400% increased histologic BE risk in nHw patients compared to AA (OR 3.949, 95% CI 3.069-5.082). In the model without the case-control study, histologic BE risk remained elevated at approximately 360% in nHw compared to AA (OR 3.618, 95% CI 2.769-4.726). Heterogeneity was not present in either model. Risk of bias was significant.

Conclusions

Histologic BE risk is elevated in nHw by 3.6-4 times compared to AA. Investigation into understanding any clinical, molecular or genetic mechanisms underlying this risk disparity is warranted.

African American ethnicity is not associated with development of Barrett's oesophagus after erosive oesophagitis

BACKGROUND

Barrett's oesophagus is the primary risk factor for oesophageal adenocarcinoma; erosive oesophagitis is considered an intermediate step with Barrett's oesophagus development potential upon healing. Barrett's oesophagus occurs in 9-19% following erosive oesophagitis but minimal data exists in African Americans. The study aim was to determine if ethnicity is associated with Barrett's oesophagus formation following erosive oesophagitis.

METHODS

Retrospective review of endoscopies from September 2007 to December 2012 was performed. Inclusion criteria were erosive oesophagitis on index endoscopy, repeat endoscopy ≥6 weeks later and non-Hispanic white or African American ethnicity. Barrett's oesophagus frequency following erosive oesophagitis by ethnicity was compared.

RESULTS

A total of 14,303 patients underwent endoscopy during the study period; 1636 had erosive oesophagitis. Repeat endoscopy was performed on 125 non-Hispanic white or African American patients ≥6 weeks from the index procedure. Barrett's oesophagus occurred in 8% of non-Hispanic whites while no African American developed it on repeat endoscopy following erosive oesophagitis (p=0.029). No significant difference was seen between ethnic groups in any clinical parameter assessed.

CONCLUSIONS

African American ethnicity appears to result in decreased Barrett's oesophagus formation following erosive oesophagitis. Further investigation to demonstrate factors resulting in decreased Barrett's oesophagus formation among African Americans should be performed.

Barrett esophagus

Although there are many unanswered questions with Barrett esophagus, we can safely say that the incidence is increasing, chemoprevention strategies for the prevention of Barrett metaplasia and its progression to adenocarcinoma may be in the offing, surveillance should be considered for all patients who are discovered to have Barrett esophagus, RFA is the treatment of choice for those with HGD and strongly considered in those with LGD, EMR should be the treatment of choice for patients with nodular high-grade Barrett esophagus, and, finally, vagal-sparing esophagectomy reserved for patients with persistent HGD or a strong suspicion of carcinoma, with consideration of a concomitant fundoplication.

Barrett's oesophagus: frequency and prediction of dysplasia and cancer

The incidence of oesophageal adenocarcinoma is continuing to increase at an alarming rate in the Western world today. Barrett's oesophagus is a clearly recognized risk factor for the development of oesophageal adenocarcinoma, but the overwhelming majority of patients with Barrett's oesophagus will never develop oesophageal cancer. A number of endoscopic, histologic and epidemiologic risk factors identify Barrett's oesophagus patients at increased risk for progression to high-grade dysplasia and oesophageal adenocarcinoma. Endoscopic factors include segment length, mucosal abnormalities as seemingly trivial as oesophagitis and the 12 to 6 o'clock hemisphere of the oesophagus. Both intestinal metaplasia and low grade dysplasia, the latter only if confirmed by a pathologist with expertise in Barrett's oesophagus pathologic interpretation are the histologic risk factors for progression. Epidemiologic risk factors include ageing, male gender, obesity, and smoking. Factors that may protect against the development of adenocarcinoma include a diet rich in fruits and vegetables, and the use of proton pump inhibitors, aspirin/NSAIDs and statins.

Barrett oesophagus: lessons on its origins from the lesion itself

Barrett oesophagus develops when the lower oesophageal squamous epithelium is replaced with columnar epithelium, which shows both intestinal and gastric differentiation. No consensus has been reached on the origin of Barrett oesophagus. Theories include a direct origin from the oesophageal-stratified squamous epithelium, or by proximal migration of the gastric cardiac epithelium with subsequent intestinalization. Variations of this theory suggest the origin is a distinctive cell at the squamocolumnar junction, the oesophageal gland ducts, or circulating bone-marrow-derived cells. Much of the supporting evidence comes from experimental models and not from studies of Barrett mucosa. In this Perspectives article, we look at the Barrett lesion itself: at its phenotype, its complexity, its clonal architecture and its stem cell organization. We conclude that Barrett glands are unique structures, but share many similarities with gastric glands undergoing the process of intestinal metaplasia. We conclude that current evidence most strongly supports an origin from stem cells in the cardia.

[Statins and gastrointestinal cancers]

The antitumour effect of statins has already been proven in animal experiments and human cancer cell lines in several gastrointestinal cancers. The chemopreventive mechanism is not completely clarified but the enhancement of oxidative stress, increased autophagy, altered expression of pro- and antiproliferative proteins and their influence on intracellular signaling pathways may play a role. Randomized studies, however, failed to confirme the expected results obtained from experimental studies. The goal of this review is to summarize the data available in the literature regarding the chemopreventive effects of statins on several gastrointestinal cancers. Results of clinical trials suggest that 10-20 mg statin daily has no or minimal antitumour effect. Chemopreventive effect of hydrophilic statins could not be detected but it seems to be significant in the case of hydrophobic statins. There are only few data available on the long-term daily use of 30-40 mg statins. Further long-term evaluation of the effect of statins regarding gastrointestinal cancers is needed, and an analysis of compound- and dose-related subgroups would be beneficial. Chemoprevention with statins cannot yet be accepted as standard medical practice. Use of statins as chemopreventive agents cannot be a substitute for regular oncological screening or surveillance.

Visceral abdominal obesity measured by CT scan is associated with an increased risk of Barrett's oesophagus: a case-control study

OBJECTIVE

Abdominal obesity has been associated with increased risk of Barrett's oesophagus (BE) but the underlying mechanism is unclear. We examined the association between visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) and the risk of BE.

DESIGN

A case-control study among eligible patients scheduled for elective oesophagastroduodenoscopy (EGD) and in a sample of patients eligible for screening colonoscopy recruited at the primary care clinic. All cases with definitive BE and a random sample of controls without BE were invited to undergo standardised mid-abdomen non-contrast computerised axial tomography images, which were analysed by semiautomated image segmentation software. The effect of VAT and SAT surface areas and their ratio (VAT to SAT) on BE were analysed in logistic regression models.

RESULTS

A total of 173 BE cases, 343 colonoscopy controls and 172 endoscopy controls underwent study EGD and CT scan. Participants with BE were more than twice as likely to be in the highest tertile of VAT to SAT ratio (OR: 2.42 (1.51 to 3.88) and adjusted OR 1.47 (0.88 to 2.45)) than colonoscopy controls, especially for those long (≥3 cm) segment BE (3.42 (1.67 to 7.01) and adjusted OR 1.93 (0.92 to 4.09)) and for white men (adjusted OR 2.12 (1.15 to 3.90)). Adjustment for gastroesophageal reflux disease (GERD) symptoms and proton pump inhibitors (PPI) use attenuated this association, but there was a significant increase in BE risk even in the absence of GERD or PPI use.

CONCLUSIONS

Large amount of visceral abdominal fat relative to subcutaneous fat is associated with a significant increase in the risk of BE. GERD may mediate some but not all of this association.

Vegetable, fruit and nitrate intake in relation to the risk of Barrett's oesophagus in a large Dutch cohort

There are few epidemiological data on the dietary risk factors of Barrett's oesophagus, a precursor of oesophageal adenocarcinoma. The present study investigated the association between vegetable, fruit and nitrate intake and Barrett's oesophagus risk in a large prospective cohort. The Netherlands Cohort Study recruited 120,852 individuals aged 55-69 years in 1986. Vegetable and fruit intake was assessed using a 150-item FFQ, and nitrate intake from dietary sources and drinking water was determined. After 16.3 years of follow-up, 433 cases (241 men and 192 women) of Barrett's oesophagus with specialised intestinal metaplasia and 3717 subcohort members were analysed in a case-cohort design using Cox proportional hazards models while adjusting for potential confounders. Men exhibited a lower risk of Barrett's oesophagus in the highest v. the lowest quintile of total (multivariable-adjusted hazard ratio (HR): 0.66, 95% CI 0.43, 1.01), raw (HR 0.63, 95% CI 0.40, 0.99), raw leafy (HR 0.55, 95% CI 0.36, 0.86) and Brassica (HR 0.64, 95% CI 0.41, 1.00) vegetable intake. No association was found for other vegetable groups and fruits. No significant associations were found between vegetable and fruit intake and Barrett's oesophagus risk among women. Total nitrate intake was inversely associated with Barrett's disease risk in men (HR 0.50, 95% CI 0.25, 0.99) and positively associated with it in women (HR 3.77, 95% CI 1.68, 8.45) (P for interaction = 0.04). These results suggest that vegetable intake may contribute to the prevention of Barrett's oesophagus. The possible differential effect in men and women should be evaluated further.

Increased risk of Barrett's esophagus among individuals born preterm or small for gestational age

BACKGROUND & AIMS

Gastroesophageal reflux is common in infants during their first year of life, especially in those born preterm or small for gestational age (SGA). We assessed whether being born preterm or SGA increased the risk of developing Barrett's esophagus (BE) in adulthood.

METHODS

We performed a population-based case-control study of patients with BE (cases) that were diagnosed at 2 Swedish hospitals from January 1, 1986, through December 31, 2005. We identified the birth hospital of the cases; data on perinatal characteristics such as gestational age at birth and birth weight were collected from original birth records. We also obtained and collected information on the 3 singleton live births, of the same sex, born after each case at the same maternity ward (controls). In total, we analyzed data from 331 cases and 852 matched controls. We used conditional logistic regression to determine odds ratios (ORs), determined 95% confidence intervals (CIs), and adjusted for potential confounding factors.

RESULTS

Compared with infants born with a normal birth weight (3000-3999 g), infants with low birth weight (<2500 g) were at increased risk of BE (adjusted OR, 8.22; 95% CI, 2.83-23.88). This was mainly due to an effect of SGA rather than preterm birth. Specifically, compared with infants with normal birth weight for gestational age (25th-75th percentiles), the odds of BE among very SGA infants (<3rd percentile) was nearly tripled (adjusted OR, 2.95; 95% CI, 1.35-6.44).

CONCLUSIONS

On the basis of a population-based study of patients with BE in Sweden, infants born SGA have a 3-fold increase in risk for developing BE as adults, compared with infants of normal birth weight for gestational age.

Obesity and gastrointestinal diseases

The prevalence of obesity in the Japanese population has been increasing dramatically in step with the Westernization of lifestyles and food ways. Our study demonstrated significant associations between obesity and a number of gastrointestinal disorders in a large sample population in Japan. We demonstrated that reflux esophagitis and hiatal hernia were strongly related to obesity (BMI > 25) in the Japanese. In particular, obesity with young male was a high risk for these diseases. On the other hand, it has been reported that obesity is also associated with Barrett's esophagus and colorectal adenoma; however, obesity was not a risk factor for these diseases in our study. The difference of ethnicity of our subjects may partly explain why we found no data to implicate obesity as a risk factor for Barrett's esophagus. Arterial sclerosis associated with advanced age and hyperglycemia was accompanied by an increased risk of colorectal adenoma.

Management strategies of Barrett's esophagus

Barrett’s esophagus is a condition resulting from chronic gastro-esophageal reflux disease with a documented risk of esophageal adenocarcinoma. Current strategies for improved survival in patients with Barrett's adenocarcinoma focus on detection of dysplasia. This can be obtained by screening programs in high-risk cohorts of patients and/or endoscopic biopsy surveillance of patients with known Barrett’s esophagus (BE). Several therapies have been developed in attempts to reverse BE and reduce cancer risk. Aggressive medical management of acid reflux, lifestyle modifications, antireflux surgery, and endoscopic treatments have been recommended for many patients with BE. Whether these interventions are cost-effective or reduce mortality from esophageal cancer remains controversial. Current treatment requires combinations of endoscopic mucosal resection techniques to eliminate visible lesions followed by ablation of residual metaplastic tissue. Esophagectomy is currently indicated in multifocal high-grade neoplasia or mucosal Barrett’s carcinoma which cannot be managed by endoscopic approach.

Barrett esophagus: what a mouse model can teach us about human disease

The incidence of esophageal adenocarcinoma (EAC) is rapidly rising in the western world and accounts for 2% of all cancer-related deaths. The precursor lesion for EAC is Barrett esophagus (BE), which is strongly associated with gastresophageal reflux disease. A major limitation to the study of EAC has been the absence of tractable and genetically modifiable preclinical models of BE. A mouse model of BE and EAC that resembles human disease could provide novel insights into the origins and molecular pathogenesis of BE. In addition, validated animal models could help stratify BE patients given the limited predictive power of current standard endoscopic measures and clinical assessment. Here, we review the findings from recently developed mouse models of BE and EAC and their impact on clinical decision making, surveillance programs and therapeutic options. The data, taken together, suggest potential origins of BE from the gastric cardia, a role of bile acid and hypergatrinemia for carcinogenesis, a growing importance for columnar-like epithelium and a critical role for Notch signaling.

Common variants at the MHC locus and at chromosome 16q24.1 predispose to Barrett's esophagus

Barrett's esophagus is an increasingly common disease that is strongly associated with reflux of stomach acid and usually a hiatus hernia, and it strongly predisposes to esophageal adenocarcinoma (EAC), a tumor with a very poor prognosis. We report the first genome-wide association study on Barrett's esophagus, comprising 1,852 UK cases and 5,172 UK controls in the discovery stage and 5,986 cases and 12,825 controls in the replication stage. Variants at two loci were associated with disease risk: chromosome 6p21, rs9257809 (Pcombined=4.09×10(-9); odds ratio (OR)=1.21, 95% confidence interval (CI)=1.13-1.28), within the major histocompatibility complex locus, and chromosome 16q24, rs9936833 (Pcombined=2.74×10(-10); OR=1.14, 95% CI=1.10-1.19), for which the closest protein-coding gene is FOXF1, which is implicated in esophageal development and structure. We found evidence that many common variants of small effect contribute to genetic susceptibility to Barrett's esophagus and that SNP alleles predisposing to obesity also increase risk for Barrett's esophagus.