Relationship between diabetes mellitus and adenocarcinoma of the oesophagus and gastric cardia

The Association between the Risk of Esophageal Cancer and Type 2 Diabetes Mellitus: An Updated Meta-Analysis

Background

A large amount of publications had reported the association between incidence of esophageal cancer (EC) and type 2 diabetes mellitus (T2DM) in the past decade. However, those papers' results are inconsistent on relationships between T2DM the incidence of EC. Therefore, the objective of this meta-analysis was to determine the relationship between T2DM and the risk of EC (including 2 histological types, esophageal adenocarcinoma [EADC] and esophageal squamous cell carcinoma [ESCC]).

Method

We finally extracted 19 articles though Pubmed, Embased, and Cochrane library. Those identify extraction date including 14,312 cases and 24,959,067 control records and then mixed the relative risks (RRs) and corresponding 95% confidence intervals (95%CIs) through STATA.

Results

We observed that there are significantly positive correlation between T2DM and EC risk (RR = 1.28, 95% CI: 1.05-1.57, P = 0.015).Also, our study showed positive correlation between T2DM and EADC (esophageal adenocarcinoma) risk (RR = 1.28, 95% CI: 1.05-1.57, P < 0.001). What's more, subgroup analysis based on ethnicity represented the Caucasian is more susceptible to EC (RR = 1.28 ,95% CI: 1.10-1.49, P = 0.001).

Conclusion

Those results offer a recent epidemiological and integrated evidence to ascertain the correlations between T2DM and incidence of EC. Those results take public health implications on preventing T2DM and then depress the occurrence of EC. Our study also provides referenced information for the prevention. However, some data is still insufficient, and more research should be carried out.

Visceral Obesity, Metabolic Syndrome, and Esophageal Adenocarcinoma

Esophageal adenocarcinoma (EAC) represents an exemplar of obesity-associated carcinogenesis, with a progressive increase in EAC risk with increased body mass index. In this context, there is increased focus on visceral adipose tissue and associated metabolic dysfunction, including hypertension, diabetes mellitus and hyperlipidemia, or combinations of these in the metabolic syndrome. Visceral obesity (VO) may promote EAC via both directly impacting on gastro-esophageal reflux disease and Barrett's esophagus, as well as via reflux-independent effects, involving adipokines, growth factors, insulin resistance, and the microbiome. In this review these pathways are explored, including the impact of VO on the tumor microenvironment, and on cancer outcomes. The current evidence-based literature regarding the role of dietary, lifestyle, pharmacologic and surgical interventions to modulate the risk of EAC is explored.

Diabetes mellitus and survival of esophageal cancer patients after esophagectomy: a systematic review and meta-analysis

Diabetes mellitus (DM) is one of the most common comorbidities in esophageal cancer patients who undergo esophagectomy. It is well established that DM has an unfavorable impact on short-term outcomes of patients with surgically treated esophageal cancer; however, whether DM has any impact on long-term survival of these patients remains unclear. We performed the first meta-analysis to investigate the impact of DM on survival of surgically treated esophageal cancer patients. We searched the following databases systematically to retrieve relevant studies on January 2, 2019: PubMed, Embase, and Web of Science. The main outcome data consisting of 3- and 5-year overall survival (OS) rates and hazard ratios (HRs) of OS were extracted to compare survival between patients with and without DM. We finally included for meta-analysis a total of eight cohort studies involving 5,044 esophageal cancer patients who underwent esophagectomy. We found no significant difference between 3-year (risk ratio [RR] = 0.94, 95% CI: 0.73-1.21; P = 0.65) and 5-year (RR = 0.92, 95% CI: 0.80-1.08; P = 0.31) OS rates between patients with and without DM after esophagectomy. Moreover, DM was not found to be an independent predictor of OS for these patients (HR = 1.10, 95% CI: 0.65-1.84; P = 0.72). Our study suggests that DM appears to have no significant impact on long-term survival of esophageal cancer patients who undergo esophagectomy. To improve the prognosis of these patients, it may be more important to control glycemic level in patients with DM who undergo esophagectomy. However, further high-quality studies with appropriate adjustment for confounding factors are needed to verify this conclusion.

Diabetes in relation to Barrett's esophagus and adenocarcinomas of the esophagus: A pooled study from the International Barrett's and Esophageal Adenocarcinoma Consortium

BACKGROUND

Diabetes is positively associated with various cancers, but its relationship with tumors of the esophagus/esophagogastric junction remains unclear.

METHODS

Data were harmonized across 13 studies in the International Barrett's and Esophageal Adenocarcinoma Consortium, comprising 2309 esophageal adenocarcinoma (EA) cases, 1938 esophagogastric junction adenocarcinoma (EGJA) cases, 1728 Barrett's esophagus (BE) cases, and 16,354 controls. Logistic regression was used to estimate study-specific odds ratios (ORs) and 95% CIs for self-reported diabetes in association with EA, EGJA, and BE. Adjusted ORs were then combined using random-effects meta-analysis.

RESULTS

Diabetes was associated with a 34% increased risk of EA (OR, 1.34; 95% CI, 1.00-1.80; I2  = 48.8% [where 0% indicates no heterogeneity, and larger values indicate increasing heterogeneity between studies]), 27% for EGJA (OR, 1.27; 95% CI, 1.05-1.55; I2  = 0.0%), and 30% for EA/EGJA combined (OR, 1.30; 95% CI, 1.06-1.58; I2  = 34.9%). Regurgitation symptoms modified the diabetes-EA/EGJA association (P for interaction = .04) with a 63% increased risk among participants with regurgitation (OR, 1.63; 95% CI, 1.19-2.22), but not among those without regurgitation (OR, 1.03; 95% CI, 0.74-1.43). No consistent association was found between diabetes and BE.

CONCLUSIONS

Diabetes was associated with increased EA and EGJA risk, which was confined to individuals with regurgitation symptoms. Lack of an association between diabetes and BE suggests that diabetes may influence progression of BE to cancer.

Association between diabetes and esophageal cancer, independent of obesity, in the United States Veterans Affairs population

In the past 30 years, the incidence of esophageal adenocarcinoma (EAC) has increased more rapidly than any other cancer in the United States. The prevalence of obesity and diabetes mellitus has drastically increased as well. We explored the potential association between obesity, diabetes mellitus, and EAC. By means of retrospective interrogation of an administrative database from fiscal year 2005-2009, we identified two cohorts. The cancer cohort was defined as patients with adenocarcinoma of the distal esophagus or gastric cardia. The comparison cohort contained patients with gastroesophageal reflux disorder (GERD; diagnosis coupled with a procedure code for fundoplication). Patient data, including demographic measures, diagnoses of obesity, diabetes mellitus, dyslipidemia, alcohol abuse, and nicotine dependence were examined. A logistic regression model identified risk factors for development of EAC. The sample included 2,836 patients identified as having either EAC (1,704) or fundoplication with GERD (1,132). Although slightly higher percentages of the benign cohort were obese, the cancer cohort had more diabetics (30.8% vs. 14.8%; chi-square = 94.5; P < 0.0001). In a logistic regression analysis adjusting for comorbidity and lifestyle factors, diagnosis of diabetes mellitus was significantly associated with esophageal cancer as opposed to GERD without cancer (OR = 2.2; 95% confidence interval [CI] 1.7-2.8). Nicotine dependence was also identified as a risk factor (OR = 1.7; 95% CI 1.4-2.0). We identified a potential association between diabetes mellitus and adenocarcinoma of the esophagus or gastric cardia. This association appears to be independent of obesity. Additionally, nicotine dependence was identified as a risk factor for EAC.

Obesity and increased risk of esophageal adenocarcinoma

There has been a substantial increase in the incidence of esophageal adenocarcinoma over the past 40 years. Meta-analyses of large prospective cohorts and population-based case-control studies demonstrate consistent associations between obesity and the development of adenocarcinoma of the esophagus and esophago-gastric junction, with an approximate doubling of risk of esophageal adenocarcinoma among patients who are obese, and an almost five-fold increased risk among those with BMI >40 kg/m². The pathologic precursor, specialized intestinal metaplasia in Barrett's esophagus, is also associated with increased adiposity. Epidemiologic evidence suggests that this cancer risk is not solely due to increased gastro-esophageal reflux, and that adipose tissue itself, in particular visceral adipose, may fuel carcinogenesis through the production of adipokines, cytokines, growth factors, and increased inflammation. The robust epidemiologic evidence linking obesity with esophageal adenocarcinoma makes it an exemplar model for investigating the molecular mechanisms underpinning obesity-associated malignant progression, which are discussed in this review.

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.

CARING (CAncer Risk and INsulin analoGues): the association of diabetes mellitus and cancer risk with focus on possible determinants - a systematic review and a meta-analysis

Background:

Patients suffering from diabetes mellitus (DM) may experience an increased risk of cancer; however, it is not certain whether this effect is due to diabetes per se.

Objective:

To examine the association between DM and cancers by a systematic review and meta-analysis according to the PRISMA guidelines.

Data Sources:

The systematic literature search includes Medline at PubMed, Embase, Cinahl, Bibliotek.dk, Cochrane library, Web of Science and SveMed+ with the search terms: “Diabetes mellitus”, “Neoplasms”, and “Risk of cancer”.

Study Eligibility Criteria:

The included studies compared the risk of cancer in diabetic patients versus non-diabetic patients. All types of observational study designs were included.

Results:

Diabetes patients were at a substantially increased risk of liver (RR=2.1), and pancreas (RR=2.2) cancer. Modestly elevated significant risks were also found for ovary (RR=1.2), breast (RR=1.1), cervix (RR=1.3), endometrial (RR=1.4), several digestive tract (RR=1.1-1.5), kidney (RR=1.4), and bladder cancer (RR=1.1). The findings were similar for men and women, and unrelated to study design. Meta-regression analyses showed limited effect modification of body mass index, and possible effect modification of age, gender, with some influence of study characteristics (population source, cancer- and diabetes ascertainment).

Limitations:

Publication bias seemed to be present. Only published data were used in the analyses.

Conclusions:

The systematic review and meta-analysis confirm the previous results of increased cancer risk in diabetes and extend this to additional cancer sites. Physicians in contact with patients with diabetes should be aware that diabetes patients are at an increased risk of cancer.

Associations of diabetes mellitus, insulin, leptin, and ghrelin with gastroesophageal reflux and Barrett's esophagus

BACKGROUND & AIMS

Insulin and leptin have proliferative and anti-apoptotic effects. Ghrelin promotes gastric emptying and secretion of growth hormone and inhibits inflammation. We assessed whether diabetes mellitus and serum levels of insulin, leptin, and ghrelin are associated with gastroesophageal reflux disease (GERD) and Barrett's esophagus.

METHODS

We conducted a case-control study in 822 men undergoing colorectal cancer screening who were recruited to also undergo upper endoscopy. We identified 70 with Barrett's esophagus; 80 additional men with Barrett's esophagus were recruited shortly after their clinical diagnoses. Serum levels of insulin, leptin, and ghrelin were assayed in all 104 fasting men with Barrett's esophagus without diabetes and 271 without diabetes or Barrett's esophagus. Logistic regression was used to estimate the effects of diabetes and levels of insulin, leptin, and ghrelin on GERD and Barrett's esophagus.

RESULTS

Among men with GERD, diabetes was inversely associated with Barrett's esophagus (adjusted odds ratio [OR] = 0.383; 95% confidence interval [CI]: 0.179-0.821). Among nondiabetics, hyperinsulinemia was positively associated with Barrett's esophagus, but the association was attenuated by adjustment for leptin and ghrelin. Leptin was positively associated with Barrett's esophagus, adjusting for obesity, GERD, and levels of insulin and ghrelin (OR for 3(rd) vs 1(st) tertile = 3.25; 95% CI: 1.29-8.17); this association was stronger in men with GERD (P = .01 for OR heterogeneity). Ghrelin was positively associated with Barrett's esophagus (OR for an increment of 400 pg/mL = 1.39; 95% CI: 1.09-1.76), but inversely associated with GERD (OR for 3(rd) vs 1(st) tertile = 0.364; 95% CI: 0.195-0.680).

CONCLUSIONS

Based on a case-control study, leptin was associated with Barrett's esophagus, particularly in men with GERD. Serum insulin level was associated with Barrett's esophagus, but might be mediated by leptin. Serum ghrelin was inversely associated with GERD, as hypothesized, but positively associated with Barrett's esophagus, contrary to our hypothesis. Additional studies are needed in men and women to replicate these findings.

Association of Barrett's esophagus with type II Diabetes Mellitus: results from a large population-based case-control study

BACKGROUND & AIMS

Central obesity could increase the risk for Barrett's esophagus (BE) and esophageal adenocarcinoma by mechanical and/or metabolic mechanisms, such as hyperinsulinemia. We performed an epidemiologic study to determine whether prior type 2 diabetes mellitus (DM2) is associated with BE.

METHODS

We performed a population-based case-control study using the General Practice Research Database, a UK primary care database that contains information on more than 8 million subjects, to identify cases of BE (using previously validated codes; n = 14,245) and matched controls without BE (by age, sex, enrollment date, duration of follow-up evaluation, and practice region by incidence density sampling; n = 70,361). We assessed the association of a prior diagnosis of DM2 with BE using conditional univariate and multivariable regression analysis. Confounders assessed included smoking, obesity measured by body mass index (BMI), and gastroesophageal reflux disease.

RESULTS

BE cases were more likely than controls to have smoked (52.4% vs 49.9%), have a higher mean BMI (27.2 vs 26.9), and a higher prevalence of DM2 than controls (5.8% vs 5.3%). On multivariable analysis, DM2 was associated with a 49% increase in the risk of BE, independent of other known risk factors (odds ratio, 1.49; 95% confidence interval, 1.16-1.91). This association was stronger in women than men. Results remained stable with sensitivity analyses.

CONCLUSIONS

In a large population-based case-control study, DM2 was a risk factor for BE, independent of obesity (as measured by BMI) and other risk factors (smoking and gastroesophageal reflux disease). These data suggest that metabolic pathways related to DM2 should be explored in BE pathogenesis and esophageal carcinogenesis.

Case-control analysis on metformin and cancer of the esophagus

PURPOSE

Metformin use has been associated with decreased cancer risks, though data on esophageal cancer are scarce. We explored the relation between use of metformin or other anti-diabetic drugs and the risk of esophageal cancer.

METHODS

We conducted a case-control analysis in the UK-based general practice research database (GPRD, now clinical practice research datalink, CPRD). Cases were individuals with an incident diagnosis of esophageal cancer between 1994 and 2010 at age 40-89 years. Ten controls per case were matched on age, sex, calendar time, general practice, and number of years of active history in the GPRD prior to the index date. Various potential confounders including diabetes mellitus, gastro-esophageal reflux, and use of proton-pump inhibitors were evaluated in univariate models, and the final results were adjusted for BMI and smoking. Results are presented as odds ratios (ORs) with 95 % confidence intervals (CI).

RESULTS

Long-term use (≥30 prescriptions) of metformin was not associated with a materially altered risk of esophageal cancer (adj. OR 1.23, 95 % CI 0.92-1.65), nor was long-term use of sulfonylureas (adj. OR 0.93, 95 % CI 0.70-1.23), insulin (adj. OR 0.87, 95 % CI 0.60-1.25), or of thiazolidinediones (adj. OR 0.71, 95 % CI 0.37-1.36).

CONCLUSION

In our population-based study, use of metformin was not associated with an altered risk of esophageal cancer.

Pre-existing diabetes mellitus increases the risk of gastric cancer: A meta-analysis

AIM: To systematically assess the association between diabetes and incidence of gastric cancer.

METHODS: We searched MedLine (PubMed), EMBASE, and the Cochrane Library without any limitations with respect to publication date or language, we also searched the references of qualifying articles. Case-control studies and cohort studies comparing the risk of gastric cancer between diabetic patients and control subjects were included. We excluded studies reporting only standardized incidence ratios without control groups and those that investigated only mortality but not incidence. Seventeen studies met our criteria, and the qualities of these studies were assessed using the Newcastle-Ottawa Quality Assessment Scale. We performed a meta-analysis of pre-existing diabetes and gastric cancer incidence using the DerSimonian-Laird method for random-effects. For subgroup analyses, we separated the studies by study type, region, sex and method to determine confounding factors and reliability. We also conducted subgroup analyses to examine the effects of smoking, Helicobacter pylori (H. pylori) infection, and cancer site. Publication bias was evaluated using Begg’s test.

RESULTS: A random-effects model meta-analysis showed an increased gastric cancer risk in diabetic patients [relative risk (RR) = 1.19; 95%CI: 1.08-1.31]. Subgroup analyses indicated that this result persisted in cohort studies (RR = 1.20; 95%CI: 1.08-1.34), in studies on populations of both Western (RR = 1.18; 95%CI: 1.03-1.36) and Eastern countries (RR = 1.19; 95%CI: 1.02-1.38), in a female subgroup (RR=1.24; 95%CI: 1.01-1.52), and in highly qualified studies (RR = 1.17; 95%CI: 1.05-1.31). Moreover, these results persisted when the analysis was confined to studies adjusted for well-known gastric cancer risk factors such as smoking (RR = 1.17; 95%CI: 1.01-1.34) and H. pylori infection (RR = 2.35; 95%CI: 1.24-4.46).

CONCLUSION: Pre-existing diabetes mellitus may increase the risk of gastric cancer by approximately 19%. This effect seems to be unrelated to geographical region.

Barrett's esophagus in Latinos undergoing endoscopy for gastroesophageal reflux disease symptoms

Previous studies comparing the prevalence of Barrett's esophagus in Latinos and non-Latino whites are inconsistent. The aim of the study is to compare the prevalence of Barrett's esophagus in Latinos and non-Latino whites and to determine risk factors associated with Barrett's esophagus. Between March 2005 and January 2009, consecutive Latino and non-Latino white patients who underwent endoscopy for primary indication for symptoms of gastroesophageal reflux disease were identified by examining the internal endoscopy database at Los Angeles County + USC Medical Center. Barrett's esophagus was defined by columnar-lined distal esophagus on endoscopy confirmed by intestinal metaplasia on histology. Clinical features and endoscopic findings were retrospectively reviewed. The mean age of the 663 patients was 50 ± 12 years, 30% were male, and 92% were Latino. Compared with non-Latino whites, Latinos had more females (72% vs. 46%; P = 0.0001) and more Helicobacter pylori infection (53% vs. 24%; P = 0.003) but less tobacco use (7% vs. 17%; P = 0.01). Overall, 10% (68/663) of all patients had Barrett's esophagus whereas the prevalence was 10% (62/611) among the Latinos and 12% (6/52) among the non-Latino whites (OR 0.9, 95% CI 0.4-2.1; P = 0.75). One patient in the Latino group had high-grade dysplasia. On multivariate analysis, male gender (AOR 2.3, 95% CI 1.4-4.1; P = 0.002), diabetes (AOR 2.2, 95% CI 1.1-4.5; P = 0.03), and age ≥55 years (AOR 2.2, 95% CI 1.3-3.8; P = 0.006) were independently associated with Barrett's esophagus; Latino ethnicity remained nonsignificant (AOR 1.1, 95% CI 0.4-2.7; P = 0.88). In Latinos undergoing endoscopy for gastroesophageal reflux disease symptoms, the prevalence of Barrett's esophagus was 10%, comparable with non-Latino white controls as well as the prevalence previously reported among Caucasians. In addition to established risk factors, diabetes was associated with Barrett's esophagus.

Risk of esophagus cancer in diabetes mellitus: a population-based case-control study in Taiwan

Background

Diabetes mellitus (DM) has been associated with the cancer risk. This study investigated relationship between DM and esophageal cancer using Taiwan’s insurance data.

Methods

We identified 549 patients with esophageal cancer newly diagnosed in 2000-2009 and randomly selected 2196 controls without any cancer, frequency matched by sex, age and diagnosis year of cases. Logistic regression model estimated odds ratios (ORs) and 95% confidence intervals (CI) of esophageal cancer associated with DM, sex, age. co-morbidities and medications.

Results

Cases were more prevalent than controls for alcoholism and esophageal disorders and using nonsteroidal anti-inflammatory drugs (NSAIDs) and cyclooxygenase-2 inhibitors but not DM. Esophageal cancer had no association with DM (OR 0.99, 95% CI 0.71-1.37), but significantly associated with alcoholism (OR 14.1, 95% CI 7.87-25.4), esophageal ulcer (OR 10.1, 95% CI 5.70-17.9), esophageal reflux (OR 3.47, 95% CI 2.14-5.26) and uses of NSAIDs (OR 2.73, 95% CI 1.80-4.13). An elevated risk of esophageal cancer appeared in DM patients taking insulin (OR 2.57, 95% CI 1.08-6.15) or sulfonyurea (OR 3.80, 95% CI 1.16-12.5).

Conclusions

Patients with DM are not at higher risk for esophagus cancer. However, esophageal disorders and anti-diabetic drugs are associated with the risk of the disease.

Diabetes and risk of esophageal and gastric adenocarcinomas

Diabetes has been consistently associated with an increased risk of liver, pancreas and endometrial cancer and has been implicated as a risk factor for esophageal and gastric cancers, although this association has been less well studied. We sought to determine the role of diabetes in the etiology of esophageal, gastric cardia and distal gastric adenocarcinomas (DGAs). This analysis included patients with esophageal adenocarcinoma (EA) (n = 209), gastric cardia adenocarcinoma (GCA) (n = 257) and DGA (n = 382), and 1,309 control participants from a population-based case-control study conducted in Los Angeles County. The study included non-Hispanic whites, African Americans, Hispanics and Asian Americans. The association of diabetes with the three tumor types was estimated using polytomous logistic regression. Odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were estimated. Nine percent of control participants and 13% of the case patients reported a history of diabetes. After adjustment for age, gender, race, birthplace, education, cigarette smoking status and body mass index, diabetes was associated with an increased risk of EA (OR, 1.48; 95% CI, 0.94-2.32; p = 0.089) and DGA (OR, 1.47; 95% CI, 1.01-2.15; p = 0.045), but was not associated with risk of GCA (OR, 0.96; 95% CI, 0.59-1.55; p = 0.87). However, the association between diabetes and risk of DGA was statistically significant only among patients for whom we interviewed their next of kin. Our study further investigated the association between diabetes and adenocarcinomas of the esophagus and distal stomach.

Barrett's esophagus: clinical features, obesity, and imaging

The following includes commentaries on clinical features and imaging of Barrett's esophagus (BE); the clinical factors that influence the development of BE; the influence of body fat distribution and central obesity; the role of adipocytokines and proinflammatory markers in carcinogenesis; the role of body mass index (BMI) in healing of Barrett's epithelium; the role of surgery in prevention of carcinogenesis in BE; the importance of double-contrast esophagography and cross-sectional images of the esophagus; and the value of positron emission tomography/computed tomography.

Risk of esophageal cancer in diabetes mellitus: a meta-analysis of observational studies

OBJECTIVE

Inconsistent findings from observational studies have prolonged the controversy over the effects of history of diabetes mellitus (DM) on the risk of esophageal cancer (EC). We conducted a meta-analysis of epidemiologic studies to evaluate the association of a history of DM with the risk of EC.

METHODS

We identified studies by a literature search of MEDLINE (from 1 January 1966) and EMBASE (from 1 January 1974), through 28 Feburary 2011, and by searching the reference lists of pertinent articles. Summary relative risks (SRRs) with 95% confidence intervals (CIs) were calculated with a random-effects model. All statistical tests were two-sided.

RESULTS

A total of 17 studies (6 case-control studies and 11 cohort studies) fulfilled the inclusion and exclusion criteria. Compared with non-diabetic individuals, diabetic individuals had a modestly increased risk of EC (SRRs 1.30, 95% CI: 1.12-1.50), with significant heterogeneity among studies (p = 0.042). In stratified analysis, the SRRs of EC were 1.28 (1.10-1.49) for diabetic men and 1.07 (95% CI, 0.71-1.62) for diabetic women, respectively. In addition, DM was associated with an increased risk of esophageal adenocarcinoma (SRR 2.12, 95% CI 1.01-4.46). There was no significant publication bias (p = 0.127 for Begg's adjusted rank correlation test and p = 0.629 for Egger's regression test).

CONCLUSION

These findings support the hypothesis that men with diabetes may have a modestly increased risk of EC, while diabetic women were not the case.

Diabetes mellitus and risk of gastric cancer: a systematic review and meta-analysis of observational studies

AIM

Increasing evidence suggests that a history of diabetes may be involved in the development of various sites of cancer. However, the association of diabetes and risk of gastric cancer (GC) remains unclear.

METHODS

We identified studies by a literature search of MEDLINE (from 1 January 1966), Web of Science (from 1 January 1994), and EMBASE (from 1 January 1974 through 31 May 2011), and by searching the reference lists of pertinent articles. All data were extracted independently by two investigators using a standardized data abstraction tool. Summary relative risks (SRRs) with 95% confidence intervals (CIs) were calculated with a random-effects model. Between-study heterogeneity was assessed using the Cochran's Q and I statistics.

RESULTS

A total of 21 studies (four case-control studies, 17 cohort studies) were included in this meta-analysis. Analysis of these 21 studies found that compared with nondiabetic individuals, diabetic individuals had a similar risk of GC (SRRs, 1.09; 95% CI: 0.98-1.22). There was strong evidence of heterogeneity among these studies (P<0.001, I²=81.2%). A subgrouped analysis found that diabetic women had 18% increased risk of GC (SRRs, 1.18; 95% CI: 1.01-1.39), whereas it was not the case with diabetic men. No significant public bias was found in this study.

CONCLUSION

These findings of this systematic review indicate that compared with nondiabetic individuals, diabetic women have an 18% increased risk of GC development. However, diabetic men have a similar risk of GC.

Prospective study of self-reported diabetes and risk of upper gastrointestinal cancers

BACKGROUND

Although gastric noncardia adenocarcinoma (GNCA) incidence rates in the United States have decreased, the rates of gastric cardia adenocarcinoma (GCA) and esophageal adenocarcinoma (EADC) have increased. Obesity increases the risks of GCA and EADC, and the associations may be partially mediated by insulin resistance. A few case-control studies have shown an association between diabetes and an increased risk of EADC.

METHODS

We prospectively examined the association between diabetes and upper gastrointestinal (UGI) cancers in a cohort of 469,448 people in the United States, ages 50 to 71 at baseline. Cox proportional hazards regression was used to estimate the HR and 95% CI for diabetes and UGI cancers, controlling for multiple potential confounders, including body mass index (BMI).

RESULTS

We observed no association of self-reported diabetes with risk of EADC, HR (95% CI) = 0.98 (0.73-1.31), esophageal squamous cell carcinoma (ESCC), HR (95% CI) = 1.02 (0.60-1.74), or GNCA, HR (95% CI) = 0.98 (0.70-1.37). However, diabetes was significantly associated with an increased risk of GCA, HR (95% CI) = 1.89 (1.43-2.50). The significant association between diabetes and risk of GCA remained after adjustment for BMI, HR (95% CI) = 1.70 (1.28-2.26) and did not differ by BMI strata (P(interaction) = 0.83). The significant association was unchanged when restricting to only overweight subjects (BMI 25 to ≤30), HR (95% CI) = 1.83 (1.18-2.85).

CONCLUSIONS

We found a significant association between self-reported diabetes and increased risk of GCA.

IMPACT

Our results suggest that the metabolic and hormonal changes related to diabetes may play a role in the etiology of GCA independently from BMI.

Does diabetes mellitus influence pathologic complete response and tumor downstaging after neoadjuvant chemoradiation for esophageal and gastroesophageal cancer? A two-institution report

BACKGROUND

Esophageal carcinoma is an aggressive disease that is often treated with neoadjuvant therapy followed by surgical resection. Diabetes mellitus (DM) has been associated with reduced efficacy of chemoradiation (CRT) in other gastrointestinal cancers. The goal of this study was to determine if DM affects response to neoadjuvant CRT in the management of gastroesophageal carcinoma.

METHODS

We retrospectively reviewed the esophageal cancer patient databases and subsequently analyzed those patients who received neoadjuvant CRT followed by surgical resection at two institutions, Thomas Jefferson University (TJUH) and Fox Chase Cancer Center (FCCC). Comparative analyses of rates of pathologic complete response rate (pCR) and pathologic downstaging in DM patients versus non-DM patients was performed.

RESULTS

Two hundred sixty patients were included in the study; 36 patients had DM and 224 were non-diabetics. The average age of the patients was 61 years (range 24-84 years). The overall pCR was 26%. The pCR rate was 19% and 27% for patients with DM and without DM, respectively (P = 0.31). Pathologic downstaging occurred in 39% of study patients, including of 33% of DM patients and 40% of non-DM patients (P = 0.42).

CONCLUSIONS

Although the current analysis does not demonstrate a significant reduction in pCR rates or pathologic downstaging in patients with DM, the observed trend suggests that a potential difference may be observed with a larger patient population. Further studies are warranted to evaluate the influence of DM on the effectiveness of neoadjuvant CRT in esophageal cancer.

Type 2 diabetes mellitus associated with increased risk for colorectal cancer: evidence from an international ecological study and population-based risk analysis in China

OBJECTIVE

To study the association between type 2 diabetes mellitus (T2DM) and colorectal cancer (CRC).

STUDY DESIGN

An international ecological study and a population-based risk analysis.

METHODS

Prevalence data for T2DM and incidence data for CRC were collected from 170 countries, and Spearman's correlation was calculated between T2DM and CRC. In the Nan-Hu district of Jia-Xing city, Zhejiang province, China, the incidence of CRC among T2DM patients between 1 January 2002 and 30 June 2002 was identified through record linkage between the Diabetic Surveillance and Registry Database with the Cancer Surveillance and Registry Database. Standardized incidence ratios (SIRs) and 95% confidence intervals were used to estimate the risk of CRC among T2DM patients.

RESULTS

Significant positive correlations (r(s)=0.534 and 0.597 in males and females, respectively) were found between the prevalence of T2DM and the incidence of CRC. Sixty-four cases of CRC were found among 7938 T2DM patients. The SIR for CRC among T2DM patients was 1.588 (95% CI 1.199-1.977). For male T2DM patients, the SIR for CRC was 1.821 (95% CI 1.234-2.408), compared with 1.364 (95% CI 0.85-1.879) among female T2DM patients. Significant increased risks for colon cancer were found, with an SIR of 1.899 (95% CI 1.139-2.658) in male T2DM patients. Female T2DM patients showed a borderline significant risk for colon cancer, with an SIR of 1.687 (95% CI 0.948-2.426). However, no significant associations were found between T2DM and risk for rectal cancer among males (SIR 1.723, 95% CI 0.786-2.66) or females (SIR 0.906, 95% CI 0.235-1.578) (all P>0.05).

CONCLUSIONS

T2DM was associated with increased risk for CRC, and this association was more evident for colon cancer and among male diabetic patients.

Does type 2 diabetes influence the risk of oesophageal adenocarcinoma?

Since hyperinsulinaemia may promote obesity-linked cancers, we compared type 2 diabetes prevalence among oesophageal adenocarcinoma (OAC) patients and population controls. Diabetes increased the risk of OAC (adjusted odds ratio 1.59, 95% confidence interval (CI) 1.04-2.43), although the risk was attenuated after further adjusting for body mass index (1.32, 95% CI 0.85-2.05).