Risk of adenocarcinomas of the oesophagus and gastric cardia in patients hospitalized for asthma

Mendelian randomization analysis of atopic dermatitis and esophageal cancer in East Asian and European populations

Background

Emerging observational studies showed an association between atopic dermatitis (AD) and gastrointestinal cancers. However, it remains unclear whether this association is causal, particularly in the case of cancers like esophageal cancer, which exhibit ancestral genetic traits.

Methods

To assess the potential causal relationship between AD and esophageal cancer across diverse ancestral backgrounds, we conducted a 2-sample Mendelian randomization study. Independent genetic instruments for AD from the FinnGen consortium (N case = 7024 and N control = 198 740), BioBank Japan (N case = 2385 and N control = 209 651) and Early Genetics and Lifecourse Epidemiology (EAGLE) eczema consortium (N case = 18 900 and N control = 84 166, without the 23andMe study) were used to investigate the association with esophageal cancer in the UK Biobank study (N case = 740 and N control = 372 016) and BioBank Japan esophageal cancer sample (N case = 1300 and N control = 197 045).

Results

When esophageal cancer extracted from East Asian ancestry was used as a outcome factor, AD data extracted from BioBank Japan (OR = 0.90, 95% CI: 0.83-0.98), FinnGen consortium (OR = 0.86, 95% CI: 0.77-0.96), and EAGLE consortium (OR = 0.92, 95% CI: 0.81-1.06) were negatively associated with esophageal cancer susceptibility. However, AD as a whole did not show an association with esophageal cancer from European ancestry.

Conclusion

This study provides support for a causal relationship between AD and esophageal cancer in East Asian populations but not between AD and esophageal cancer from European ancestry. The specific associations between esophageal cancer and AD appear to exhibit significant disparities between the East Asian and European regions.

Causal relationship between lung diseases and risk of esophageal cancer: insights from Mendelian randomization

BACKGROUND

An increasing number of cohort studies have indicated a correlation between lung diseases and esophageal cancer, but the exact causal relationship has not been definitively established. Therefore, the objective of this study is to assess the causal relationship between lung diseases and esophageal cancer.

METHODS

Single-nucleotide polymorphisms (SNPs) related to lung diseases such as asthma, chronic obstructive pulmonary disease (COPD), lung cancer, and idiopathic pulmonary fibrosis (IPF), along with outcomes data on esophageal cancer, were extracted from public genome-wide association studies (GWAS). A two-sample Mendelian randomization (MR) analysis was then performed using publicly available GWAS data to investigate the potential causal relationship. The effect estimates were primarily calculated using the fixed-effects inverse-variance-weighted method.

RESULTS

Totally, 81 SNPs related to asthma among 218,792 participants in GWAS. Based on the primary causal effects model using MR analyses with the inverse variance weighted (IVW) method, asthma was demonstrated a significantly related to the risk of esophageal cancer (OR 1.0006; 95% CI 1.0003-1.0010, p = 0.001), while COPD (OR 1.0306; 95% CI 0.9504-1.1176, p = 0.466), lung cancer (OR 1.0003, 95% CI 0.9998-1.0008, p = 0.305), as well as IPF (OR 0.9999, 95% CI 0.9998-1.0000, p = 0.147), showed no significant correlation with esophageal cancer.

CONCLUSIONS

The two-sample MR analysis conducted in this study revealed a positive causal relationship between asthma and esophageal cancer. In contrast, esophageal cancer demonstrated no significant correlation with COPD, lung cancer, or IPF. Further large-sample prospective studies are needed to validate these findings and to provide appropriate recommendations regarding esophageal cancer screening among patients with asthma.

Current status and perspectives regarding the association between allergic disorders and cancer

While activation of immune system may lead to a lower risk of some diseases, it has been shown that a history of atopic allergic disorders such as asthma, hay fever, eczema, and food allergies could be related to several types of cancer. However, the evidence is not entirely conclusive. Two proposals suggest a possible mechanism for the association between allergic disorders and cancers: immune surveillance and the antigenic stimulation. The association of allergy and cancer may vary by cancer site and the type of exposure. The aim of current review was to summarize the current knowledge of the association between allergic diseases and the risk of cancers with particular emphasis on case-controls and cohort studies to estimate the cancer risk associated with allergy.

Medications that relax the lower oesophageal sphincter and risk of oesophageal cancer: An analysis of two independent population-based databases

Excessive lower oesophageal sphincter relaxation increases gastro-oesophageal acid reflux, an oesophageal adenocarcinoma risk factor. Medications that relax this sphincter (benzodiazepines, calcium channel blockers, nitrates, β2 agonists and xanthines) could promote cancer. These medications were investigated in two independent datasets. In the Scottish Primary Care Clinical Informatics Unit (PCCIU) database, a nested case-control study of oesophageal cancer was performed using GP prescription records. Conditional logistic regression was used to calculate odds ratios (OR) and 95% confidence intervals (CIs) for medication use and oesophageal cancer. In UK Biobank, a cohort study was conducted using self-reported medication use. Cox regression was used to calculate hazard ratios (HRs) and 95% CIs for medication use and oesophageal cancer, and by tumour subtype. Overall, 1,979 oesophageal cancer patients were matched to 9,543 controls in PCCIU, and 355 of 475,768 participants developed oesophageal cancer in UK Biobank. None of the medications investigated were significantly associated with oesophageal cancer risk apart from β2 agonists, which were associated with increased oesophageal cancer risk in PCCIU (adjusted OR 1.38, 95% CI 1.12, 1.70) but not in UK Biobank (adjusted HR 1.21, 95% CI 0.70, 2.08). Medications that relax the lower oesophageal sphincter were not associated with oesophageal cancer, apart from β2 agonists. This increased cancer risk in β2 agonist users merits further investigation.

Epidemiology, Diagnosis, and Management of Esophageal Adenocarcinoma

Esophageal adenocarcinoma (EAC) is rapidly increasing in incidence in Western cultures. Barrett's esophagus is the presumed precursor lesion for this cancer. Several other risk factors for this cancer have been described, including chronic heartburn, tobacco use, white race, and obesity. Despite these known associations, most patients with EAC present with symptoms of dysphagia from late-stage tumors; only a small number of patients are identified by screening and surveillance programs. Diagnostic analysis of EAC usually commences with upper endoscopy followed by cross-sectional imaging. Endoscopic ultrasonography is useful to assess the local extent of disease as well as the involvement of regional lymph nodes. T1a EAC may be treated endoscopically, and some patients with T1b disease may also benefit from endoscopic therapy. Locally advanced disease is generally managed with esophagectomy, often accompanied by neoadjuvant chemoradiotherapy or chemotherapy. The prognosis is based on tumor stage; patients with T1a tumors have an excellent prognosis, whereas few patients with advanced disease have long-term survival.

Cancer risk and mortality in asthma patients: A Swedish national cohort study

BACKGROUND

Previous studies found an increased risk of cancer in hospitalized asthma patients, but it is not known whether patients from primary health care show a similar risk pattern. In addition, it is unclear whether the diagnosis of asthma can influence the prognosis of subsequent cancer.

METHODS

Asthma patients were identified from Swedish inpatient, outpatient, and primary health care registers, and were linked to the Swedish Cancer Registry to identify subsequent diagnoses of cancer. Standardized incidence ratios (SIRs) were used to examine the risk of cancer in asthma patients compared with subjects without asthma. In addition, we used Cox proportional hazards regression to estimate hazard ratios (HRs) for mortality in patients with both asthma and cancer.

RESULTS

A total of 10 649 cancers were diagnosed in patients with previous asthma, with a SIR of 1.19 (95% CI 1.17-1.21). A total of 15 cancer sites showed an increased incidence, whereas two cancer sites showed a decreased risk. Non-allergic asthma showed the highest risk of cancer (SIR = 1.25, 95% CI 1.18-1.32), followed by unspecified asthma (SIR = 1.22, 95% CI 1.19-1.25), status asthmaticus (SIR = 1.19, 95% CI 1.02-1.39), and allergic asthma (SIR = 1.14, 95% CI 1.06-1.22). The risk of cancer was similarly increased in asthma patients diagnosed in primary health care and those diagnosed in hospitals. Cancer patients with previous asthma had increased mortality, with a HR of 1.55 (95% CI 1.50-1.60). HRs ranged from 1.09 to 1.94 for different sites/types of cancer.

CONCLUSIONS

Patients with asthma, irrespective of whether they were treated in primary health care or hospitals, had an increased risk of cancer. In addition, cancer patients with previous asthma had a worse prognosis compared with those without asthma, suggesting that these patients may require a multidisciplinary approach to manage the comorbidity.

Environmental causes of esophageal cancer

This article reviews the environmental risk factors and predisposing conditions for the two main histologic types of esophageal cancer. Tobacco smoking, excessive alcohol consumption, drinking maté, low intake of fresh fruits and vegetables, achalasia, and low socioeconomic status increase the risk of esophageal squamous cell carcinoma. Results of investigations on other potential risk factors, including opium consumption, intake of hot drinks, eating pickled vegetables, poor oral health, and exposure to human papillomavirus, polycyclic aromatic hydrocarbons, N-nitroso compounds, acetaldehyde, and fumonisins are discussed. Gastroesophageal reflux, obesity, tobacco smoking, hiatal hernia, achalasia, and, probably, absence of H pylori in the stomach increase the risk of esophageal adenocarcinoma. Results of studies investigating other factors are also discussed.

Cancer risk in hospitalised asthma patients

Asthma is an increasingly common disorder, affecting 5–10% of the population. It involves a dysregulated immune function, which may predispose to subsequent cancer. We examined cancer risk among Swedish subjects who had hospital admission once or multiple times for asthma. An asthma research database was created by identifying asthma patients from the Swedish Hospital Discharge Register and by linking them with the Cancer Registry. A total of 140 425 patients were hospitalised for asthma during 1965–2004, of whom 7421 patients developed cancer, giving an overall standardised incidence ratio (SIR) of 1.36. A significant increase was noted for most sites, with the exception of breast and ovarian cancers and non-Hodgkin's lymphoma and myeloma. Patients with multiple hospital admissions showed a high risk, particularly for stomach (SIR 1.70) and colon (SIR 1.99) cancers. A significant decrease was noted for endometrial cancer and skin melanoma. Oesophageal and lung cancers showed high risks throughout the study period, whereas stomach cancer increased towards the end of the period. The relatively stable temporal trends suggest that the asthmatic condition rather than its medication is responsible for the observed associations.

A systematic review of the safety of topical therapies for atopic dermatitis

BACKGROUND

The safety of topical therapies for atopic dermatitis (AD), a common and morbid disease, has recently been the focus of increased scrutiny, adding confusion as how best to manage these patients.

OBJECTIVES

The objective of these systematic reviews was to determine the safety of topical therapies for AD.

METHODS

Databases searched included: OVID Medline, Medline In-Process and Other Non-Indexed Citations, Embase, and the Cochrane Central Register of Controlled Trials. In addition to the articles identified by this search, investigators were also referred to a list of links (most recently updated 25 September 2005) to recent Food and Drug Administration (FDA) studies, reports and meetings regarding the topical calcineurin inhibitors for further potential references. Only fully published papers available in English and data obtained from FDA sites were included. Furthermore, the criteria for inclusion and exclusion for each systematic review were further evaluated at a meeting of all of the content and evidence-based medicine experts participating in this process and alteration of the inclusion criteria was done at that time when it was felt necessary to avoid inclusion of lower-quality data in the review. Qualitative review of the abstracted data was performed and reviewed at a meeting of all of the content and evidence-based medicine experts.

RESULTS

While systemic exposure to these topical agents does occur, physiological changes appear to be uncommon and systemic complications rare and have only been found with use of topical corticosteroids.

CONCLUSIONS

Based on the data that are available the overall safety of AD therapies appears to be good with the only documented systemic side-effects of therapy those occasionally seen with use of topical corticosteroids.

An overview of the association between allergy and cancer

Numerous epidemiological studies have evaluated some aspect of the association between a history of allergy and cancer occurrence. In this article, an overview of the epidemiological evidence is presented with a discussion of a number of methodological issues important in this area of study. Literature searches were conducted using the MEDLINE database from 1966 through to August 2005 to identify articles that explored a personal history of allergic disorders as a risk factor for cancer. Although it is difficult to draw conclusions between allergy and cancer at many sites because of insufficient evidence or a lack of consistency both within and among studies completed to date, strong inverse associations have been reported for pancreatic cancer and glioma, whereas lung cancer was positively associated with asthma. Additional studies are needed to confirm these finding and to address the limitations of previous studies, including the validity and reliability of exposure measures and control for confounding. Further, large prospective studies using cancer incidence would be particularly useful, including studies using biological markers of allergic status to reduce potential misclassification and to confirm the results of previous studies based on self-report. There is also a need for further basic research to clarify a potential mechanism, should an association exist.

Controversies surrounding body mass, reflux, and risk of oesophageal adenocarcinoma

At first the association between body mass, reflux, and oesophageal adenocarcinoma might seem easily interpreted, but a more thorough assessment of the published work shows that several factors are missing. Reflux and obesity are established risk factors for oesophageal adenocarcinoma, particularly when they occur in combination. However, the interplay between these and other factors with regard to oesophageal adenocarcinoma is uncertain. Moreover, the contribution of these risk factors in explaining the increasing incidence of oesophageal adenocarcinoma is unclear, because the trends in prevalence of reflux and obesity do not match those of incidence of oesophageal adenocarcinoma. Moreover, none of these factors contribute strongly to the striking predominance of oesophageal adenocarcinoma in men. Thus, several factors that can explain the development of oesophageal adenocarcinoma need to be addressed.

Surgical therapy for Barrett's esophagus

Given the anatomic and functional defects almost universally present in patients who have BE, antireflux surgery is the most reliable means of stopping acid and nonacid (alkaline) reflux. Because patients who have BE have end-stage GERD, they require durable and reliable control of reflux, and the Hill procedure and partial fundoplication are associated with unacceptably high failure rates. In addition, there is mounting evidence that the success rates for Nissen fundoplication are lower in patients who have BE than in patients who have less severe GERD. Given that the most common mode of failure of a laparoscopic Nissen fundoplication is herniation of the fundoplication into the chest, patients who have BE must be considered at risk for having a short esophagus. The failure rate may be reduced by the liberal addition of a Collis gastroplasty, but the long-term consequences of acid-secreting mucosa left above the fundoplication in patients who have BE remain unclear. Patients suspected of having a short esophagus on the basis of a large hiatal hernia, stricture, or long-segment BE should be considered for a transthoracic approach to their fundoplication, as this affords good esophageal mobilization and may obviate the need for a gastroplasty. Surgeons must pay particular attention to their own and published results and continue to refine the operation to maximize the likelihood of a good outcome in this difficult group of patients. It is only with excellent control of reflux that any differences in the risk of progression to dysplasia and cancer become apparent, and significant, between medically and surgically treated patients.

Review article: gastro-oesophageal reflux disease -- how wide is its span?

Symptoms of gastro-oesophageal reflux disease are highly prevalent in Western countries; however, it is less certain how many individuals with heartburn have clinically relevant disease. Although the prevalence of gastro-oesophageal reflux disease in Asia is substantially lower, the incidence may be increasing. How much of this increase is explained by the increasing recognition of heartburn in clinical practice, dietary changes and increasing obesity, or the eradication of Helicobacter pylori, remains unclear. There has been speculation that endoscopy-negative reflux disease represents a separate entity from reflux oesophagitis (as defined by the Los Angeles classification), but the evidence that might support this proposal is unconvincing. Patients with chronic reflux symptoms have a higher risk of Barrett's oesophagus, and the increased risk of developing oesophageal adenocarcinoma in individuals with a long history of heartburn is also well documented, but whether this always occurs via Barrett's oesophagus is debatable. Moreover, treatment with standard-dose antisecretory therapies and anti-reflux surgery seems unlikely, based on current evidence, to reduce the cancer risk in patients with Barrett's oesophagus. Gastro-oesophageal reflux disease has also been implicated in an increasing array of other conditions, but arguably in these settings it is often over-diagnosed.

Laryngopharyngeal reflux symptoms better predict the presence of esophageal adenocarcinoma than typical gastroesophageal reflux symptoms

OBJECTIVE

To determine whether the presence of laryngopharyngeal reflux symptoms is associated with the presence of esophageal adenocarcinoma (EAC).

BACKGROUND

Most patients diagnosed with EAC have incurable disease at the time of detection. The majority of these patients are unaware of the presence of Barrett's esophagus prior to cancer diagnosis and many do not report typical symptoms of gastroesophageal reflux disease (GERD). This suggests that the current GERD symptom-based screening paradigm may be inadequate. Data support a causal relation between complicated GERD and laryngopharyngeal reflux symptoms. We theorize that laryngopharyngeal reflux symptoms are not recognized expeditiously, resulting in chronic esophageal injury and an unrecognized progression of Barrett's esophagus to EAC.

METHODS

This is a case-comparison (control) study. Cases were patients diagnosed with EAC (n = 63) between 1997 and 2002. Three comparison groups were selected: 1) Barrett's esophagus patients without dysplasia (n = 50), 2) GERD patients without Barrett's esophagus (n = 50), and 3) patients with no history of GERD symptoms or antisecretory medication use (n = 56). The risk factors evaluated included demographics, medical history, lifestyle variables, and laryngopharyngeal reflux symptoms. Typical GERD symptoms and antisecretory medication use were recorded. Multivariate analysis of demographics, comorbid risk factors, and symptoms was performed with logistic regression to provide odds ratios for the probability of EAC diagnosis.

RESULTS

The prevalence of patients with laryngopharyngeal reflux symptoms was significantly greater in the cases than comparison groups (P = 0.0005). The prevalence of laryngopharyngeal reflux symptoms increased as disease severity progressed from the non-GERD comparison group (19.6%) to GERD (26%), Barrett's esophagus (40%), and EAC patients (54%). Symptoms of GERD were less prevalent in cases (43%) when compared with Barrett's esophagus (66%) and GERD (86%) control groups (P < 0.001). Twenty-seven percent (17 of 63) of EAC patients never had GERD or laryngopharyngeal reflux symptoms. Fifty-seven percent of EAC patients presented without ever having typical GERD symptoms. Chronic cough, diabetes, and age emerged as independent risk factors for the development of EAC.

CONCLUSIONS

Symptoms of laryngopharyngeal reflux are more prevalent in patients with EAC than typical GERD symptoms and may represent the only sign of disease. Chronic cough is an independent risk factor associated with the presence of EAC. Addition of laryngopharyngeal reflux symptoms to the current Barrett's screening guidelines is warranted.

Comparison of comorbidity prevalence in oesophageal and gastric carcinoma patients: a population-based study

OBJECTIVE

We investigated the distribution of serious comorbidity in patients with newly diagnosed oesophageal and gastric cancer between 1993 and 2001. Our special interest was comparing distal oesophageal and gastric cardia adenocarcinoma patients since a common origin of these tumours has been suggested.

METHODS

Data on comorbidity (previous cancers, chronic obstructive pulmonary diseases, cardiovascular and cerebrovascular diseases, hypertension, ulcerative digestive tract diseases, liver diseases and diabetes) were derived from a population-based database in The Netherlands to compare risk factor profiles for 479 oesophageal squamous cell carcinomas, 339 distal oesophageal adenocarcinomas, 570 cardia adenocarcinomas and 1965 subcardia cancers.

RESULTS

A comparable age and gender distribution was shown in distal oesophageal and cardia adenocarcinoma patients. After adjustment for age and gender, only the prevalence of previous cancers differed between adenocarcinomas of distal oesophagus and cardia [more frequent in distal oesophageal adenocarcinoma patients, odds ratio (OR) = 1.84, P = 0.01]. Ulcerative and liver diseases were more prevalent in oesophageal squamous cell carcinoma patients as compared with distal oesophageal adenocarcinoma patients (OR = 1.90, P = 0.02 and OR = 8.82, P = 0.04, respectively), whereas diabetes was more prevalent in the latter (OR = 0.56, P = 0.03). Cardia adenocarcinoma patients significantly more often had hypertension as compared with subcardia cancer patients (OR = 1.53, P = 0.001), whereas the latter more often suffered from previous cancers and ulcerative diseases (OR = 0.54, P = 0.0009 and OR = 0.25, P < 0.0001, respectively).

CONCLUSIONS

In terms of comorbidity at diagnosis, cardia adenocarcinoma patients resemble distal oesophageal adenocarcinoma patients rather than gastric subcardia carcinoma patients, with likewise equal age and gender distribution.

Allergy and the risk of selected digestive and laryngeal neoplasms

The relation between allergy and cancer has been investigated within an integrated series of case-control studies of digestive tract and laryngeal neoplasms conducted in Italy since the early 1990s. These included 598 patients with incident, histologically confirmed cancer of the oral cavity and pharynx, 304 of the oesophagus, 1225 of the colon, 728 of the rectum, 460 of the larynx and 4999 controls, selected among patients admitted to the same network of hospitals as cases for acute, non-neoplastic diseases. Inverse associations with history of allergy were found for all cancer sites examined (odds ratio=0.44 for oral cavity and pharynx, 0.80 for oesophagus, 0.76 for colon, 0.54 for rectum and 0.33 for larynx). The associations were consistent in strata of age and sex, and when subjects with a first diagnosis of allergy 5 or more years before cancer diagnosis or hospital admission were considered. The present study therefore provides further evidence for a possible protective effect of prior history of allergy on cancer risk.

Risk factors for the gastric cardia cancer: a case-control study in Fujian Province

AIM

The incidence of gastric cardia cancer has greatly increased in the past 2-3 decades, however, the risk factors for the disease are still not clearly understood. The investigations among Chinese population on the risk factors of gastric cardia cancer were also scarcely reported. We therefore conducted a case-control study in Fujian province, China, to investigate the potential risk and protective factors of this disease.

METHODS

191 cardia and 190 non-cardia gastric cancer cases, and a total of 222 control cases were included in this study. Standard questionnaires were used in collecting epidemiological factors and the data were then analyzed by the unconditional logistic regression model.

RESULTS

As the factors such as age, gender, smoking, alcohol consumption, and family history of gastric cancer were controlled, a multivariable analysis was conducted, which revealed that there was a significant correlation between the dietary habits such as irregular meal, over and fast eating, and the gastric cardia cancer with the odds ratios (ORs) of 4.2 (95 % confidence interval: 2.3-7.7), 4.7 (2.1-10.8), and 2.7 (1.3-5.3) respectively. Other correlations were also observed between the gastric cardia cancer and the consumption of salty fish or pickled vegetable, smoking, and the family cancer history with the ORs of 5.5 (1.4-19.5), 1.8 (1.0-3.0), 2.1 (1.3-3.5), and 3.8 (2.3-6.2) respectively. In contrast, the negative correlations were found existing between the intake of fresh vegetables and fruits, the use of refrigerator, and the gastric cardia cancer, with the ORs of 0.4 (0.2-0.9), 0.2 (0.1-0.5), and 0.2 (0.1-0.4), respectively. However, dietary habits were associated less with non-cardia gastric cancer compared with its cardia counterpart.

CONCLUSION

Dietary habits might be one of the risk factors for the cardia carcinogenesis among Chinese population.