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

Comparative effectiveness of sodium-glucose cotransporter-2 inhibitors for new-onset gastric cancer and gastric diseases in patients with type 2 diabetes mellitus: a population-based cohort study

OBJECTIVE

To compare the risks of gastric cancer and other gastric diseases in patients with type-2 diabetes mellitus (T2DM) exposed to sodium-glucose cotransporter 2 inhibitors (SGLT2I), dipeptidyl peptidase-4 inhibitors (DPP4I) or glucagon-like peptide-1 receptor agonists (GLP1a).

DESIGN

This was a population-based cohort study of prospectively collected data on patients with T2DM prescribed SGLT2I, DPP4I or GLP1a between January 1st 2015 and December 31st 2020 from Hong Kong. The outcomes were new-onset gastric cancer, peptic ulcer (PU), acute gastritis, non-acute gastritis, and gastroesophageal reflux disease (GERD). Propensity score matching (1:1) using the nearest neighbour search was performed, and multivariable Cox regression was applied. A three-arm comparison between SGLT2I, DPP4I and GLP1a was conducted using propensity scores with inverse probability of treatment weighting.

RESULTS

A total of 62,858 patients (median age: 62.2 years old [SD: 12.8]; 55.93% males; SGLT2I: n = 23,442; DPP4I: n = 39,416) were included. In the matched cohort, the incidence of gastric cancer was lower in SGLT2I (Incidence rate per 1000 person-year, IR: 0.32; 95% confidence interval, CI 0.23-0.43) than in DPP4I (IR per 1000 person-year: 1.22; CI 1.03-1.42) users. Multivariable Cox regression found that SGLT2I use was associated with lower risks of gastric cancer (HR 0.30; 95% CI 0.19-0.48), PU, acute gastritis, non-acute gastritis, and GERD (p < 0.05) compared to DPP4I use. In the three-arm analysis, GLP1a use was associated with higher risks of gastric cancer and GERD compared to SGLT2I use.

CONCLUSIONS

The use of SGLT2I was associated with lower risks of new-onset gastric cancer, PU, acute gastritis, non-acute gastritis, and GERD after matching and adjustments compared to DPP4I use. SGLT2I use was associated with lower risks of GERD and gastric cancer compared to GLP1a use.

Identification of potential shared gene signatures between gastric cancer and type 2 diabetes: a data-driven analysis

Background

Gastric cancer (GC) and type 2 diabetes (T2D) contribute to each other, but the interaction mechanisms remain undiscovered. The goal of this research was to explore shared genes as well as crosstalk mechanisms between GC and T2D.

Methods

The Gene Expression Omnibus (GEO) database served as the source of the GC and T2D datasets. The differentially expressed genes (DEGs) and weighted gene co-expression network analysis (WGCNA) were utilized to identify representative genes. In addition, overlapping genes between the representative genes of the two diseases were used for functional enrichment analysis and protein-protein interaction (PPI) network. Next, hub genes were filtered through two machine learning algorithms. Finally, external validation was undertaken with data from the Cancer Genome Atlas (TCGA) database.

Results

A total of 292 and 541 DEGs were obtained from the GC (GSE29272) and T2D (GSE164416) datasets, respectively. In addition, 2,704 and 336 module genes were identified in GC and T2D. Following their intersection, 104 crosstalk genes were identified. Enrichment analysis indicated that "ECM-receptor interaction," "AGE-RAGE signaling pathway in diabetic complications," "aging," and "cellular response to copper ion" were mutual pathways. Through the PPI network, 10 genes were identified as candidate hub genes. Machine learning further selected BGN, VCAN, FN1, FBLN1, COL4A5, COL1A1, and COL6A3 as hub genes.

Conclusion

"ECM-receptor interaction," "AGE-RAGE signaling pathway in diabetic complications," "aging," and "cellular response to copper ion" were revealed as possible crosstalk mechanisms. BGN, VCAN, FN1, FBLN1, COL4A5, COL1A1, and COL6A3 were identified as shared genes and potential therapeutic targets for people suffering from GC and T2D.

Big data approach in the field of gastric and colorectal cancer research

Big data is characterized by three attributes: volume, variety,, and velocity. In healthcare setting, big data refers to vast dataset that is electronically stored and managed in an automated manner and has the potential to enhance human health and healthcare system. In this review, gastric cancer (GC) and postcolonoscopy colorectal cancer (PCCRC) will be used to illustrate application of big data approach in the field of gastrointestinal cancer research. Helicobacter pylori (HP) eradication only reduces GC risk by 46% due to preexisting precancerous lesions. Apart from endoscopy surveillance, identifying medications that modify GC risk is another strategy. Population-based cohort studies showed that long-term use of proton pump inhibitors (PPIs) associated with higher GC risk after HP eradication, while aspirin and statins associated with lower risk. While diabetes mellitus conferred 73% higher GC risk, metformin use associated with 51% lower risk, effect of which was independent of glycemic control. Nonetheless, nonsteroidal anti-inflammatory drugs (NA-NSAIDs) are not associated with lower GC risk. CRC can still occur after initial colonoscopy in which no cancer was detected (i.e. PCCRC). Between 2005 and 2013, the rate of interval-type PCCRC-3y (defined as CRC diagnosed between 6 and 36 months of index colonoscopy which was negative for CRC) was 7.9% in Hong Kong, with >80% being distal cancers and higher cancer-specific mortality compared with detected CRC. Certain clinical and endoscopy-related factors were associated with PCCRC-3 risk. Medications shown to have chemopreventive effects on PCCRC include statins, NA-NSAIDs, and angiotensin-converting enzyme inhibitors/angiotensin receptor blockers.

Diabetes Mellitus and Gastric Cancer: Correlation and Potential Mechanisms

This review summarizes the correlation between diabetes mellitus (DM) and gastric cancer (GC) from the perspectives of epidemiology, drug use, and potential mechanisms. The association between DM and GC is inconclusive, and the positive direction of the association reported in most published meta-analyses suggests that DM may be an independent risk factor for GC. Many clinical investigations have shown that people with DM and GC who undergo gastrectomy may have better glycemic control. The potential link between DM and GC may involve the interaction of multiple common risk factors, such as obesity, hyperglycemia and hyperinsulinemia, H. pylori infection, and the use of metformin. Although in vitro and in vivo data support that H. pylori infection status and metformin can influence GC risk in DM patients, there are conflicting results. Patient survival outcomes are influenced by multiple factors, so further research is needed to identify the patients who may benefit.

Systemic Diseases and Gastrointestinal Cancer Risk

Importance

Gastrointestinal (GI) cancers are the second leading cause of cancer-related deaths worldwide.

Observations

The global challenges GI cancers pose are high, especially in middle- and low-income countries. Patients with these cancers present with symptoms of poor appetite, weight loss, heartburn, abdominal pain, fatigue and anaemia. Several risk factors contribute to GI cancers, including age, gender, obesity, pathogenic infections, smoking cigarettes, alcohol consumption and dietary habits. Most of these cancers are sporadic. However, some patients are at high risk due to a family history of GI cancers. Systemic diseases affect multiple organs, and their chronic occurrence elicits inflammatory responses at various sites. These diseases also contribute to GI cancers.

Conclusion and Relevance

In this review, we discuss that untreated systemic diseases, including diabetes, hepatitis, acquired immune deficiency syndrome, ulcers and hypertension, can potentially lead to GI cancers if they remain untreated for a longer period. Systemic diseases initiate oxidative stress, inflammatory pathways and genetic manipulations, which altogether confer risks to GI cancers. Here, we describe the association between systemic diseases and their underlying mechanisms leading to GI cancers.

Circulating Proteins and Metabolite Biomarkers in Gastric Cancer: A Systematic Review and Meta-analysis

BACKGROUND

Gastric cancer (GC) is often diagnosed at an advanced stage and thus patients have a poor prognosis. This implies that early detection of this cancer will improve patient prognosis and survival. This systematic review explored the association of circulating protein and metabolite biomarkers with GC development.

METHODS

A literature search was conducted until November 2021 on Medline, Embase, Cochrane library, and Web of Science databases. Studies were included if they assessed circulating proteins and metabolites in blood, urine, or saliva and determined their association with GC risk. Quality of identified studies was determined using the Newcastle-Ottawa scale for cohort studies. Random and fixed effects meta-analyses were performed to calculate pooled odds ratio.

RESULTS

A total of 53 studies were included. High levels of anti-Helicobacter pylORi IgG levels, pepsinogen I (PGI) <30 µg/L and serum pepsinogen I/ pepsinogen II (PGI/II) ratio<3 were positively associated with risk of developing GC (pooled odds ratio (OR): 2.70; 95% CI: 1.44-5.04, 5.96, 95% CI: 2.65-13.42 and 4.43; 95% CI: 3.04-6.47). In addition, an inverse relationship was found between ferritin, iron and transferrin levels and risk of developing GC (OR: 0.62; 95% CI: 0.38-1,0.97; 95% CI: 0.94-1 and 0.85; 95% CI: 0.76-0.94). However, there was no association between levels of glucose, cholesterol, vitamin C, vitamin B12, vitamin A, α-Carotene, β-Carotene, α-Tocopherol, γ-Tocopherol, and GC risk.

CONCLUSION

The pooled analysis demonstrated that high levels of anti-Helicobacter pylORi IgG, PGI<30µg/L and serum PGI/II ratio <3 and low levels of ferritin, iron and transferrin were associated with risk of GC.

Factors Associated With Geographic Disparities in Gastrointestinal Cancer Mortality in the United States

BACKGROUND & AIMS

Significant geographic variability in gastrointestinal (GI) cancer-related death has been reported in the United States. We aimed to evaluate both modifiable and nonmodifiable factors associated with intercounty differences in mortality due to GI cancer.

METHODS

Data from the Centers for Disease Control and Prevention's Wide-ranging Online Data for Epidemiologic Research platform were used to calculate county-level mortality from esophageal, gastric, pancreatic, and colorectal cancers. Multivariable linear regression models were fit to adjust for county-level covariables, considering both patient (eg, sex, race, obesity, diabetes, alcohol, and smoking) and structural factors (eg, specialist density, poverty, insurance prevalence, and colon cancer screening prevalence). Intercounty variability in GI cancer-related mortality explained by these covariables was expressed as the multivariable model R².

RESULTS

There were significant geographic disparities in GI cancer-related county-level mortality across the US from 2010-2019 with the ratio of mortality between 90th and 10th percentile counties ranging from 1.5 (pancreatic) to 2.1 (gastric cancer). Counties with the highest 5% mortality rates for gastric, pancreatic, and colorectal cancer were primarily in the Southeastern United States. Multivariable models explained 43%, 61%, 14%, and 39% of the intercounty variability in mortality rates for esophageal, gastric, pancreatic, and colorectal cancer, respectively. Cigarette smoking and rural residence (independent of specialist density) were most strongly associated with GI cancer-related mortality.

CONCLUSIONS

Both patient and structural factors contribute to significant geographic differences in mortality from GI cancers. Our findings support continued public health efforts to reduce smoking use and improve care for rural patients, which may contribute to a reduction in disparities in GI cancer-related death.

The association between diabetes and gastric cancer: results from the Stomach Cancer Pooling Project Consortium

BACKGROUND

Prior epidemiologic studies on the association between diabetes and gastric cancer risk provided inconclusive findings, while traditional, aggregate data meta-analyses were characterized by high between-study heterogeneity.

OBJECTIVE

To investigate the association between type 2 diabetes and gastric cancer using data from the 'Stomach Cancer Pooling (StoP) Project', an international consortium of more than 30 case-control and nested case-control studies, which is large and provides harmonized definition of participants' characteristics across individual studies. The data have the potential to minimize between-study heterogeneity and provide greater statistical power for subgroup analysis.

METHODS

We included 5592 gastric cancer cases and 12 477 controls from 14 studies from Europe, Asia, North America, and South America in a two-stage individual-participant data meta-analysis. Random-effect models were used to estimate summary odds ratios (ORs) and their corresponding 95% confidence intervals (CIs) by pooling study-specific ORs.

RESULTS

We did not find an overall association between diabetes and gastric cancer (pooled OR = 1.01, 95% CI, 0.94-1.07). However, the risk of cardia gastric cancer was significantly higher among individuals with type 2 diabetes (OR = 1.16, 95% CI, 1.02-1.33). There was no association between diabetes and gastric cancer risk in strata of Helicobacter pylori infection serostatus, age, sex, BMI, smoking status, alcohol consumption, fruit/vegetable intake, gastric cancer histologic type, and source of controls.

CONCLUSION

This study provides additional evidence that diabetes is unrelated to gastric cancer overall but may be associated with excess cardia gastric cancer risk.

Cancer and its predictors in Chinese adults with newly diagnosed diabetes and impaired glucose tolerance (IGT): a 30-year follow-up of the Da Qing IGT and Diabetes Study

Background

We aimed to explore if hyperglycaemia and hyperinsulinemia in the diabetes and prediabetes population were associated with increased risk of cancer occurence.

Methods

Overall, 1700 participants with different glycaemic statuses were screened from the 110,660 residents of Da-Qing, China, in 1985. They were followed up to 30 years to access cancer outcomes.

Results

Cancer was identified in 15.2% (259/1700) of the participants. The incidence of cancer in the normal glucose tolerance (NGT), impaired glucose tolerance (IGT) and diabetes groups was 6.06, 6.77, and 7.18 per 1000 person-years, respectively (P = 0.02). In the Fine-Gray model with all cause death as competing risk, compared with the NGT controls, both IGT and diabetes groups demonstrated significantly higher risk of cancer (for the IGT group, adjusted hazard ratio (aHR) = 1.77, 95% CI 1.38–2.27, P < 0.0001; for the diabetes, aHR = 3.34, 95% CI 2.64–4.22, P < 0.0001). Among the IGT participants, progress to diabetes (aHR = 2.28, 95%CI 1.24–4.20, P = 0.008) and insulin-area under the curve at baseline (for 1 SD increase, aHR = 1.39, P = 0.02) were also associated with the risk of cancer after adjustment of covariables.

Conclusions

Hyperglycaemia in patients with diabetes, hyperinsulinemia, and progression to diabetes in people with IGT is significantly associated with the long-term increased risk of cancer occurrence.

Haemoglobin A1c and serum glucose levels and risk of gastric cancer: a systematic review and meta-analysis

Background

This systematic review and meta-analysis examined associations between serum levels of haemoglobin A1c (HbA1c) and glucose and the risk of gastric cancer.

Methods

MEDLINE, Embase, and Cochrane Library were searched for studies examining associations between serum levels of HbA1c or glucose and the risk of gastric cancer. Inclusion of studies, quality assessment, and data extraction were conducted independently by two authors. Pooled hazard ratios (HR) with 95% confidence intervals (CI) were synthesised using random-effects models. Cochran’s Q test and I² statistic were used to assess heterogeneity.

Results

Among 3473 identified studies, 12 were included. Of these, 5 studies examined HbA1c levels and 7 studies examined serum glucose levels. Serum HbA1c levels >6% were associated with an increased risk of gastric cancer (HR 1.36, 95% CI 1.06–1.74). When compared with the lowest glucose categories, the highest glucose categories were associated with a borderline increased risk of gastric cancer (HR 1.11, 95% CI 0.98–1.26). In subgroup analyses, studies that adjusted for Helicobacter pylori infection indicated stronger associations between elevated HbA1c levels and gastric cancer (HR 2.08, 95% CI 1.46–2.98) than those without such adjustment (HR 1.10, 95% CI 0.91–1.32).

Conclusions

Long-standing poor glycaemic control may increase the risk of gastric cancer.

Registration number

PROSPERO CRD42020157453.

Association of Diabetes Mellitus and Alcohol Abuse with Cancer: Molecular Mechanisms and Clinical Significance

Diabetes mellitus (DM), one of the metabolic diseases which is characterized by sustained hyperglycemia, is a life-threatening disease. The global prevalence of DM is on the rise, mainly in low- and middle-income countries. Diabetes is a major cause of blindness, heart attacks, kidney failure, stroke, and lower limb amputation. Type 2 diabetes mellitus (T2DM) is a form of diabetes that is characterized by high blood sugar and insulin resistance. T2DM can be prevented or delayed by a healthy diet, regular physical activity, maintaining normal body weight, and avoiding alcohol and tobacco use. Ethanol and its metabolites can cause differentiation defects in stem cells and promote inflammatory injury and carcinogenesis in several tissues. Recent studies have suggested that diabetes can be treated, and its consequences can be avoided or delayed with proper management. DM has a greater risk for several cancers, such as breast, colorectal, endometrial, pancreatic, gallbladder, renal, and liver cancer. The incidence of cancer is significantly higher in patients with DM than in those without DM. In addition to DM, alcohol abuse is also a risk factor for many cancers. We present a review of the recent studies investigating the association of both DM and alcohol abuse with cancer incidence.

Metabolic Effects of Gastrectomy and Duodenal Bypass in Early Gastric Cancer Patients with T2DM: A Prospective Single-Center Cohort Study

We evaluated the metabolic effects of gastrectomies and endoscopic submucosal dissections (ESDs) in early gastric cancer (EGC) patients with type 2 diabetes mellitus (T2DM). Forty-one EGC patients with T2DM undergoing gastrectomy or ESD were prospectively evaluated. Metabolic parameters in the patients who underwent gastrectomy with and without a duodenal bypass (groups 1 and 2, n = 24 and n = 5, respectively) were compared with those in patients who underwent ESD (control, n = 12). After 1 year, the proportions of improved/equivocal/worsened glycemic control were 62.5%/29.2%/8.3% in group 1, 40.0%/60.0%/0.0% in group 2, and 16.7%/50.0%/33.3% in the controls, respectively (p = 0.046). The multivariable ordered logistic regression analysis results showed that both groups had better 1-year glycemic control. Groups 1 and 2 showed a significant reduction in postprandial glucose (−97.9 and −67.8 mg/dL), body mass index (−2.1 and −2.3 kg/m²), and glycosylated hemoglobin (group 1 only, −0.5% point) (all p < 0.05). Furthermore, improvements in group 1 were more prominent when preoperative leptin levels were high (p for interaction < 0.05). Metabolic improvements in both groups were also observed for insulin resistance, leptin, plasminogen activator inhibitor-1, and resistin. Gastrectomy improved glycemic control and various metabolic parameters in EGC patients with T2DM. Patients with high leptin levels may experience greater metabolic benefits from gastrectomy with duodenal bypass.

Hyperglycemia Promotes Liver Metastasis of Colorectal Cancer via Upregulation of Integrin αvβ6

Background

Diabetes is related to higher risk of multiple cancers. This study aimed to explore the effect and mechanism of diabetes on liver metastasis of CRC.

Material/Methods

Overall and liver metastasis-free survival in diabetic and non-diabetic CRC patients were compared by Kaplan-Meier analysis. Expression of αvβ6 was detected by immunohistochemistry in clinical specimens. Effects of hyperglycemia on αvβ6 expression in colon cancer cells were assessed by western blot, real-time PCR, and flowcytometry. Effects of hyperglycemia on migration and invasion were demonstrated by Transwell assay. Expression and activity of MMP-9 and MMP-2 were determined by real-time PCR and gelatin zymography. Liver metastatic nodules were counted and β6 expression was detected by western blot in a liver metastasis mouse model.

Results

CRC patients with diabetes had poorer overall and liver metastasis-free survival, and diabetes was associated with higher αvβ6 expression in CRC specimens. Hyperglycemia promoted the invasion and migration of colon cancer cells, and upregulated the expression and activity of MMP-9, which were attenuated by inhibition of αvβ6. Hyperglycemia upregulated the expression of β6 and cell surface expression of αvβ6, which was reduced by ERK inhibitor. The in vitro results were confirmed in vivo in the mouse model.

Conclusions

Our study demonstrated the enhancing effect of hyperglycemia on liver metastasis of CRC, and showed that αvβ6 was involved in this process, suggesting that control of glucose levels and inhibition of αvβ6 can reduce the risk of liver metastasis in diabetic CRC patients.

The Relationship between Diabetes Mellitus and Gastric Cancer and the Potential Benefits of Metformin: An Extensive Review of the Literature

The objective of this review is to summarize the findings of published research that investigated the relationship between diabetes mellitus and gastric cancer (GCa) and the potential benefits of metformin on GCa. Related literature has been extensively reviewed, and findings from studies investigating the relationship between diabetes mellitus and GCa suggest that hyperglycemia, hyperinsulinemia and insulin resistance are closely related to the development of GCa. Although not supported by all, most observational studies suggest an increased risk of GCa in patients with type 2 diabetes mellitus, especially in women and in Asian populations. Incidence of second primary malignancy diagnosed after GCa is significantly higher in diabetes patients. Diabetes patients with GCa may have more complications after gastrectomy or chemotherapy and they may have a poorer prognosis than patients with GCa but without diabetes mellitus. However, glycemic control may improve in the diabetes patients with GCa after receiving gastrectomy, especially after procedures that bypass the duodenum and proximal jejunum, such as Roux-en-Y gastric bypass or Billroth II reconstruction. The potential links between diabetes mellitus and GCa may involve the interactions with shared risk factors (e.g., obesity, hyperglycemia, hyperinsulinemia, insulin resistance, high salt intake, smoking, etc.), Helicobacter pylori (HP) infection, medications (e.g., insulin, metformin, statins, aspirin, proton pump inhibitors, antibiotics, etc.) and comorbidities (e.g., hypertension, dyslipidemia, vascular complications, heart failure, renal failure, etc.). With regards to the potential benefits of metformin on GCa, results of most observational studies suggest a reduced risk of GCa associated with metformin use in patients with T2DM, which can be supported by evidence derived from many in vitro and animal studies. Metformin use may also reduce the risk of HP infection, an important risk factor of GCa. In patients with GCa, metformin users may have improved survival and reduced recurrence. More studies are required to clarify the pathological subtypes/anatomical sites of GCa associated with type 2 diabetes mellitus or prevented by metformin, to confirm whether GCa risk can also be increased in patients with type 1 diabetes mellitus and to explore the possible role of gastric microbiota in the development of GCa.

Chemopreventive Effect of Metformin on Gastric Cancer Development

Although Helicobacterpylori infection is the most important causative factor for gastric cancer (GC), H. pylori eradication alone does not completely eliminate the GC risk. In addition to H. pylori eradication, other risk factors for GC should be identified and targeted. Diabetes mellitus (DM) confers a 20% increased risk of GC, which could be mediated via several biological mechanisms including the stimulation of cell proliferation via hyperinsulinemia and increased insulin-growth factor production, the promotion of angiogenesis, and DNA damage. With a current global prevalence of 9.3% and a predicted rise to 10.2% by 2030, DM could contribute substantially to the burden of GC cases worldwide. Emerging evidence showed that metformin possesses chemopreventive effects via both direct (e.g., adenosine monophosphate-activated protein kinase activation and subsequent inhibition of the mammalian target of rapamycin pathway) and indirect (e.g., modulation of the interaction between tumor cells and their microenvironment and gut microbiota) pathways. A recent meta-analysis of observational studies showed that metformin use was associated with 24% lower GC risk. However, many available observational studies related to metformin effects suffered from biases including the failure to adjust for the H. pylori infection status and serial glycemic control and time-related biases. Future prospective studies addressing these pitfalls are needed.

Evaluating the effect of diabetes on the prognosis of gastric cancer using a propensity score matching method

Background

Gastric cancer (GC) is one of the malignant tumors with high incidence in China. At present, the relationship between type 2 diabetes (T2DM) and the therapeutic effect of various malignant tumors has attracted more and more attention. This study aimed to investigate whether T2DM is a prognostic factor for patients with GC.

Methods

Patients who had GC and who were admitted to our hospital from November 2008 to December 2015 were included in the study. Among these patients, 84 patients GC complicated with T2DM (GC + T2DM) were enrolled in the observation group, and 215 patients with normal blood glucose were enrolled in the control group. Patients' general information was collected by referring to their electronic and paper medical records, and their living status was followed up by conducting a telephone survey, referring to their hospitalization record, and performing an outpatient review. A propensity score matching method was used to select a 1:1 matched control for each patient with GC and diabetes. An overall survival curve was established using the Kaplan-Meier method. The survival rate was compared via a log-rank test. A Cox proportional hazards regression model was used to the analyse single and multiple factors affecting patient outcomes.

Results

Before matching was conducted, the differences in gender, stage, treatment, and comorbidity were found to be statistically significant (P>0.05). After matching was completed, the clinical data and pathological differences between the two groups were not statistically significant (P<0.05). A histogram matching the pre- and post-propensity scores showed that the matching was successful. The results of the Cox regression model revealed that grouping, pathological type, and treatment were the independent risk factors of the survival of patients with GC. Survival analysis found that the 3-year, 5-year, and overall survival rates of the observation group were significantly lower than those of the control group (P<0.05).

Conclusions

T2DM plays an important role in the development of GC, and is a prognostic factor among patients with GC.

Guidelines for endoscopic diagnosis of early gastric cancer

The Japan Gastroenterological Endoscopy Society developed the Guideline for Endoscopic Diagnosis of Early Gastric Cancer based on scientific methods. Endoscopy for the diagnosis of early gastric cancer has been acknowledged as a useful and highly precise examination, and its use has become increasingly more common in recent years. However, the level of evidence in this field is low, and it is often necessary to determine recommendations based on expert consensus only. This clinical practice guideline consists of the following sections to provide the current guideline: [I] Risk stratification of gastric cancer before endoscopic examination, [II] Detection of early gastric cancer, [III] Qualitative diagnosis of early gastric cancer, [IV] Diagnosis to choose the therapeutic strategy for gastric cancer, [V] Risk stratification after endoscopic examination, and [VI] Surveillance of early gastric cancer.

Metformin Use and Gastric Cancer Risk in Diabetic Patients After Helicobacter pylori Eradication

BACKGROUND

Although prior studies showed metformin could reduce gastric cancer (GC) risk in patients with diabetes mellitus, they failed to adjust for Helicobacter pylori infection and glycemic control. We aimed to investigate whether metformin reduced GC risk in H. pylori-eradicated diabetic patients and its association with glycemic control.

METHODS

This was a territory-wide cohort study using hospital registry database, recruiting all diabetic patients who were prescribed clarithromycin-based triple therapy for H. pylori infection from 2003 to 2012. Subjects were observed from H. pylori therapy prescription until GC diagnosis, death, or end of study (December 2015). Exclusion criteria included GC diagnosed within first year of H. pylori therapy, prior history of GC or gastrectomy, and failure of H. pylori eradication. The hazard ratio (HR) of GC with metformin (defined as at least 180-day use) was estimated by Cox model with propensity score adjustment for covariates (age, sex, comorbidities, medications [including insulin], and time-weighted average hemoglobin A1c [HbA1c]). All statistical tests were two-sided.

RESULTS

During a median follow-up of 7.1 years (IQR = 4.7-9.8), 37 (0.51%) of 7266 diabetic patients developed GC at a median age of 76.4 years (IQR = 64.8-81.5 years). Metformin use was associated with a reduced GC risk (adjusted HR = 0.49, 95% CI = 0.24 to 0.98). There was a trend towards a lower GC risk with increasing duration (Ptrend = .01) and dose of metformin (Ptrend = .02). HbA1c level was not an independent risk factor for GC.

CONCLUSIONS

Metformin use was associated with a lower GC risk among H. pylori-eradicated diabetic patients in a duration- and dose-response manner, which was independent of HbA1c level.

The development and tailoring of a peer support program for patients with diabetes mellitus and depression in a primary health care setting in Central Uganda

BACKGROUND

About 20-40% of patients with diabetes mellitus (DM) suffer from depressive disorders (DD) during the course of their illness. Despite the high burden of DD among patients with DM, it is rarely identified and adequately treated at the majority of primary health care clinics in sub-Saharan Africa (SSA). The use of peer support to deliver components of mental health care have been suggested in resource constrained SSA, even though its acceptability have not been fully examined.

METHODS

We conducted qualitative interviews (QI) to assess the perceptions of DM patients with an experience of suffering from a DD about the acceptability of delivering peer support to patients with comorbid DM and DD. We then trained them to deliver peer support to DM patients who were newly diagnosed with DD. We identified challenges and potential barriers to a successful implementation of peer support, and generated solutions to these barriers.

RESULTS

Participants reported that for one to be a peer, they need to be mature in age, consistently attend the clinics/keep appointments, and not to be suffering from any active physical or co-morbid mental or substance abuse disorder. Participants anticipated that the major barrier to the delivery of peer support would be high attrition rates as a result of the difficulty by DM patients in accessing the health care facility due to financial constraints. A potential solution to this barrier was having peer support sessions coinciding with the return date to hospital. Peers reported that the content of the intervention should mainly be about the fact that DM was a chronic medical condition for which there was need to adhere to lifelong treatment. There was consensus that peer support would be acceptable to the patients.

CONCLUSION

Our study indicates that a peer support program is an acceptable means of delivering adjunct care to support treatment adherence and management, especially in settings where there are severe staff shortages and psycho-education may not be routinely delivered.

MorbiNet: multimorbidity networks in adult general population. Analysis of type 2 diabetes mellitus comorbidity

Multimorbidity has great impact on health care. We constructed multimorbidity networks in the general population, extracted subnets focused on common chronic conditions and analysed type 2 diabetes mellitus (T2DM) comorbidity network. We used electronic records from 3,135,948 adult people in Catalonia, Spain (539,909 with T2DM), with at least 2 coexistent chronic conditions within the study period (2006-2017). We constructed networks from odds-ratio estimates adjusted by age and sex and considered connections with OR > 1.2 and p-value < 1e-5. Directed networks and trajectories were derived from temporal associations. Interactive networks are freely available in a website with the option to customize characteristics and subnets. The more connected conditions in T2DM undirected network were: complicated hypertension and atherosclerosis/peripheral vascular disease (degree: 32), cholecystitis/cholelithiasis, retinopathy and peripheral neuritis/neuropathy (degree: 31). T2DM has moderate number of connections and centrality but is associated with conditions with high scores in the multimorbidity network (neuropathy, anaemia and digestive diseases), and severe conditions with poor prognosis. The strongest associations from T2DM directed networks were to retinopathy (OR: 23.8), glomerulonephritis/nephrosis (OR: 3.4), peripheral neuritis/neuropathy (OR: 2.7) and pancreas cancer (OR: 2.4). Temporal associations showed the relevance of retinopathy in the progression to complicated hypertension, cerebrovascular disease, ischemic heart disease and organ failure.

Impact of metabolically healthy obesity on the risk of incident gastric cancer: a population-based cohort study

BACKGROUND

The risk of colon or breast cancer in metabolically healthy obese (MHO) were lower than that in metabolically abnormal obese (MAO). We hypothesized that the risk of incident gastric cancer in MHO is lower than that in MAO.

METHODS

This historical cohort study included 19,685 Japanese individuals who received health-checkup programs from 2003 to 2016. Each subject was classified as metabolically healthy (MH) (no metabolic abnormalities) or metabolically abnormal (MA) (one or more metabolic abnormalities), according to four metabolic factors (hypertension, impaired fasting glucose, hypertriglyceridemia and low HDL-cholesterol). Obese (O) or non-obese (NO) was classified by a BMI cutoff of 25.0 kg/m². Hazard ratios of metabolic phenotypes for incident gastric cancer were calculated by the Cox proportional hazard model with adjustments for age, sex, alcohol consumption, smoking and exercise.

RESULTS

Over the median follow-up period of 5.5 (2.9-9.4) years, incident rate of gastric cancer was 0.65 per 1000 persons-years. Incident rate of MHNO, MHO, MANO and MAO were 0.33, 0.25, 0.80 and 1.21 per 1000 persons-years, respectively. Compared with MHNO, the adjusted hazard ratios for development of gastric cancer were 0.69 (95% CI 0.04-3.39, p = 0.723) in MHO, 1.16 (95% CI 0.63-2.12, p = 0.636) in MANO and 2.09 (95% CI 1.10-3.97, p = 0.024) in MAO.

CONCLUSIONS

This study shows that individuals with MAO, but not those with MHO, had an elevated risk for incident gastric cancer. Thus, we should focus more on the presence of metabolic abnormalities rather than obesity itself for incident gastric cancer.

Impact of diabetes on prognosis of gastric cancer patients performed with gastrectomy

Objective

This study aimed to determine the impact of type 2 diabetes mellitus (T2DM) on clinical outcomes of gastric cancer (GC) patients and explore whether metformin use and good glycemic control could reverse it.

Methods

Clinicopathologic data of consecutive GC patients who underwent gastrectomy at Nanfang Hospital between October 2004 and December 2015 were included. Propensity score matching (PSM) was performed to balance the important factors of the disease status between non-T2DM and T2DM group. The last follow-up time was January 2019.

Results

A total of 1,692 eligible patients (1,621 non-T2DM vs. 71 T2DM) were included. After PSM, non-T2DM group (n=139) and T2DM group (n=71) were more balanced in baseline variables. The 5-year cancer-specific survival (CSS) rate in T2DM group (47.0%) was inferior to that in non-T2DM group (58.0%), but did not reach statistical significance [hazard ratio (HR)=1.319, 95% confidence interval (95% CI): 0.868−2.005, P=0.192]. While the 5-year progress-free survival (PFS) rate of T2DM group (40.6%) is significantly worse than that in non-T2DM group (56.3%) (HR=1.516, 95% CI: 1.004−2.290, P=0.045). Univariate and multivariate analyses showed that T2DM was an independent risk factor for PFS but not for CSS. In T2DM group, metformin use subgroup was associated with superior 5-year CSS and PFS in compared with non-metformin use subgroup, although the difference was not statistically significant (5-year CSS: 48.0%vs. 45.4%, HR=0.680, 95% CI: 0.352−1.313, P=0.246; 5-year PFS: 43.5%vs. 35.7%, HR=0.763, 95% CI: 0.400−1.454, P=0.406). The 5-year CSS rate was 47.5% in good glycemic control subgroup and 44.1% in poor glycemic control subgroup (HR=0.826, 95% CI: 0.398−1.713, P=0.605). And both two subgroups yielded a similar 5-year PFS rate (42.2%vs. 36.3%, HR=0.908, 95% CI: 0.441−1.871, P=0.792).

Conclusions

DM promoted disease progress of GC after gastrectomy but had not yet led to the significant discrepancy of CSS. For GC patients with T2DM, metformin use was associated with superior survival but without statistical significance, while better glycemic control could not improve the prognosis.

Statins Were Associated with a Reduced Gastric Cancer Risk in Patients with Eradicated Helicobacter Pylori Infection: A Territory-Wide Propensity Score Matched Study

BACKGROUND

Individuals may still develop gastric cancer even after Helicobacter pylori eradication. We aimed to investigate statin effect on gastric cancer development in H. pylori-eradicated subjects.

METHODS

All adult subjects who were prescribed clarithromycin-based triple therapy between 2003 and 2012 were identified in this retrospective cohort study utilizing a territory-wide electronic healthcare database. Patients were observed from index date of H. pylori therapy, and censored at gastric cancer diagnosis, death, or December 2015 (study end date). Statin use was defined as ≥180-day use after index date. Exclusion criteria included gastric cancer diagnosed within the first year after index date, previous gastric cancer or gastrectomy, and H. pylori treatment failure. Subdistribution hazard ratio (SHR) of gastric cancer with statins was calculated by competing risk regression with propensity score (PS) analysis matching 19 variables (age, sex, comorbidities, and other drug usage, including proton pump inhibitors, nonsteroidal anti-inflammatory drugs, aspirin, cyclooxygenase-2 inhibitors, and metformin).

RESULTS

During a median follow-up of 7.6 years (interquartile range = 5.1-10.3), 169 (0.27%) of 63,605 patients developed gastric cancer at an incidence rate of 3.5 per 10,000 person-years. Among 22,870 PS-matched subjects, statins were associated with a lower gastric cancer risk (SHR = 0.34; 95% confidence interval, 0.19-0.61), in a duration- and dose-response manner (P _trend < 0.05).

CONCLUSIONS

Statins were associated with a lower gastric cancer risk in a duration- and dose-response manner among H. pylori-eradicated patients.

IMPACT

This study provides evidence on the additional benefits of statins as chemopreventive agents against gastric cancer among H. pylori-eradicated patients.

Diabetes Increases Risk of Gastric Cancer After Helicobacter pylori Eradication: A Territory-Wide Study With Propensity Score Analysis

OBJECTIVE

Whether diabetes mellitus (DM) increases risk of gastric cancer (GC) remains controversial because of inadequate adjustments for important risk factors, including Helicobacter pylori (HP) infection status, concomitant medication use, and cancer site. We investigated whether type 2 DM increased risk of GC in patients after they received treatment for HP infection.

RESEARCH DESIGN AND METHODS

This was a territory-wide cohort study of patients aged ≥45 years who had received clarithromycin-based triple therapy for HP infection between 2003 and 2012 in Hong Kong. Data were retrieved from a public electronic health database. Observation started from receipt of therapy for HP infection to GC diagnosis, death, or the end of the study (December 2015). Exclusion criteria included type 1 DM, GC diagnosed within the 1st year of HP therapy, prior GC or gastrectomy, and retreatment for HP infection. The adjusted hazard ratio (aHR) of GC with type 2 DM was calculated by using a Cox model that adjusted for 20 covariates (age, sex, comorbidities, and medications) through propensity score regression.

RESULTS

During a median follow-up of 7.1 years (interquartile range 4.8-9.3 years), 153 of 46,460 patients (0.33%) developed GC at a median age of 72.4 years. Type 2 DM was associated with an increased risk of GC (aHR 1.73 [95% CI 1.08-2.79]). Stratified analysis showed an increase in risk for cardia cancer only (aHR 3.40 [95% CI 1.45-7.97]) and in those with suboptimal DM control (time-weighted mean HbA_1c ≥6.0% [42 mmol/mol]; aHR 1.68 [95% CI 1.07-2.63]).

CONCLUSIONS

Type 2 DM is associated with an increased risk of GC among patients in whom HP was eradicated, in particular gastric cardia cancer and in those with suboptimal DM control.

Recent evidence on modifiable and non-modifiable risk factors for colorectal cancer (CRC): a systematic synopsis of meta-analyses from 2015 to 2017

Colorectal cancer (CRC) is a common cancer with a huge impact on international public health. This review discusses recent evidence on modifiable and non-modifiable risk factors for CRC using a systematic review method. This systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines on systematic reviews and meta-analyses of observational studies. The literature search was performed on the Ovid MEDLINE database and included publications from 2015 to 2017, followed by a quality assessment and a narrative synthesis. Of the 90 identified articles, there were 13 meta-analyses with statistically significant results. Seven articles discussed modifiable risk factors and six articles discussed non-modifiable risk. The modifiable risk factors with the highest risk were radiotherapy of prostate cancer (pooled odds ratio 1.68; 95% confidence interval [CI] 1.33–2.12). The non-modifiable risk factors with the highest risk was Lynch syndrome (hazard ratio 135.49; 95% CI 111.55–164.57). This review discovered new and previously known risk factors for CRC. Recent evidence shows that research on CRC risk factors is continuing to grow indicating that more studies on risk factors are needed to optimize CRC prevention and early detection.

Retrospective database analysis of cancer risk in patients with type 2 diabetes mellitus in China

OBJECTIVE

To investigate the association between type 2 diabetes (T2D) and the risk of overall cancer and site-specific cancers in a Chinese population.

RESEARCH DESIGN AND METHODS

Tianjin Urban Employee Basic Medical Insurance database (2003-2014) was used to identify patients with newly onset T2D in 2009, patients with prevalent T2D prior to 2009, and general individuals without T2D. Overall and site-specific cancer incidence rates and incidence rate ratios relative to general population were calculated for both incident and prevalent T2D cohorts. Multivariate Cox proportional hazards models adjusting for baseline characteristics and potential bias were conducted. Subgroup analyses based on gender and age were further conducted.

RESULTS

For the year 2009, 21,208 patients with onset T2D (mean age 58.8 years; 48.1% female), 28,248 patients with prevalent T2D (mean age 63.7 years; 50.2% female) and 744,339 general individuals (mean age 43.2 years; 47.7% female) were identified. Controlling for confounders, diabetic patients had an overall 56%-59% higher risk of developing cancer, among which the highest risks by site were liver (adjusted hazard ratio [aHR] = 1.80-2.48), colorectal (aHR = 2.41-2.69) and stomach (aHR = 2.02-2.51) cancers (all p < .05). Patients with prevalent T2D had increased cancer risk in the pancreas (aHR = 4.52, p < .001). Female diabetic patients had increased risk in the kidneys (aHR = 3.22-3.31, p < .01). Patients aged between 50 and 59 years had the highest relative risk (90% higher), while the relative risk was the lowest among patients ≥70 (45% higher).

CONCLUSION

Type 2 diabetes was associated with increased overall cancer risk led by liver, colorectal and stomach cancers. Patients with longer diabetes duration were associated with higher pancreatic cancer risk and female diabetic patients had a higher risk of kidney cancer.

Risk of gastric cancer development after eradication of Helicobacter pylori

Helicobacter pylori (H. pylori) infection is the most important risk factor for gastric cancer (GC) development through the Correa’s gastric carcinogenesis cascade. However, H. pylori eradication alone does not eliminate GC, as pre-neoplastic lesions (atrophic gastritis, intestinal metaplasia and dysplasia) may have already developed in some patients. It is therefore necessary to identify patients at high-risk for gastric cancer after H. pylori eradication to streamline the management plan. If the patients have not undergone endoscopy with histologic assessment, the identification of certain clinical risk factors and non-invasive testing (serum pepsinogen) can predict the risk of atrophic gastritis. For those with suspected atrophic gastritis, further risk stratification by endoscopy with histologic assessment according to validated histologic staging systems would be advisable. Patients with higher stages may require long-term endoscopic surveillance. Apart from secondary prevention to reduce deaths by diagnosing GC at an early stage, identifying medications that could potentially modify the GC risk would be desirable. The potential roles of a number of medications have been suggested by various studies, including proton pump inhibitors (PPIs), aspirin, statins and metformin. However, there are currently no randomized clinical trials to address the impact of these medications on GC risk after H. pylori eradication. In addition, most of these studies failed to adjust for the effect of concurrent medications on GC risk. Recently, large population-based retrospective cohort studies have shown that PPIs were associated with an increased GC risk after H. pylori eradication, while aspirin was associated with a lower risk. The roles of other agents in reducing GC risk after H. pylori eradication remain to be determined.

Association between Helicobacter pylori Infection and Cardiovascular Risk Factors among Patients in the Northern Part of Afghanistan: a Cross-Sectional Study in Andkhoy City

Background: The association between Helicobacter pylori infection and cardiovascular risk factors remains controversial. The high prevalence of H. pylori infection among Afghan patients warranted the investigation of this association. The aim of the present study was to determine the association between H. pylori infection and cardiovascular risk factors among patients visiting an outpatient clinic in Andkhoy, Afghanistan. Methods: We performed a cross-sectional study of 271 consecutive patients in an outpatient clinic in Andkhoy, Afghanistan from April 2017 to June 2017. The diagnosis of H. pylori infection was achieved using an enzyme-linked immunosorbent assay test. The patients were divided into H. pylori positive (n=189) and H. pylori negative (n=82) groups. The association between H. pylori infection and cardiovascular risk factors was analyzed. Results: Of the total 271 study participants, 102 (37.6%) were male and 169 (62.4%) female. The mean age ± standard deviation of the patients who were H. pylori-positive and H. pylori-negative was 51.0 ± 17.6 years and 51.6 ± 17.6 years, respectively. In multivariate logistic regression analyses, H. pylori infection was significantly associated with diabetes mellitus (DM) (odds ratio [OR] 3.16, 95% confidence interval [CI] 1.31-7.62, P = 0.011), and body mass index (BMI) levels (OR 1.17, 95% CI 108-1.26, P < 0.001). Conclusions: Our study indicated that H. pylori infection was significantly associated with DM and elevated BMI levels in patients from an outpatient clinic in Andkhoy, Afghanistan. More aggressive measures, including DM, obesity control, and H. pylori eradication are needed.

Diabetes mellitus and the risk of gastric cancer: a meta-analysis of cohort studies

Studies examining the relationship between diabetes mellitus (DM) and the risk of gastric cancer incidence or gastric cancer mortality have produced inconsistent results. The purpose of this study was to evaluate the evidence regarding the relationship between DM and subsequent gastric cancer incidence or gastric cancer mortality risk on the basis of cohort studies. A systematic search of articles in PubMed, EmBase, the Cochrane Library, and reference lists was conducted to identify relevant literature. Twenty-two cohort studies reporting data on 8,559,861 participants were included in the study. Overall, participants with DM had little or no change in the risk of gastric cancer, or gastric cancer mortality. There was no evidence of difference in the RR for gastric cancer between men and women. Participants with DM had a non-significant trend towards an increased risk of gastric cancer mortality in men. There was no significant difference between men and women for this relationship. Finally, although subgroup analysis suggested DM was associated with a significant impact on gastric cancer incidence and gastric cancer mortality risk in several specific populations, a significance based on gender difference was not observed. In conclusion, DM might increase the risk of gastric cancer in men when the study used standard incidence/mortality ratio as effect estimate. Further, DM were associated with higher risk of gastric cancer mortality in men if the mean age at baseline less than 55.0 years, used RR or HR as effect estimate, the study adjusted smoking or not, and the study not adjusted alcohol drinking.

Diabetes in midlife and risk of cancer in late life: A nationwide Swedish twin study

The association between diabetes and cancer risk remains controversial. Hence, we examined whether midlife diabetes is related to the risk of cancer in late-life, and whether genetic and early-life environmental factors play a role in this association. This study included 25,154 twin individuals born in 1958 or earlier from the Swedish Twin Registry. Information on cancer diagnosis in late life (aged ≥ 65) during 1998-2014, was derived from the National Patient and Cancer Registries. Diabetes was ascertained based on self- or informant-reported history, patient registry and antidiabetic medication use. Midlife diabetes was defined when diabetes was diagnosed before 65 years. Data were analyzed following two strategies: (i) unmatched case-control analysis for all participants using generalized estimating equation (GEE) models, and (ii) co-twin control analysis for cancer-discordant twin pairs using conditional logistic regression. Overall, 1,766 (7.0%) had midlife diabetes and 5,293 (21.0%) had cancer in late-life. In multiadjusted GEE models, the odds ratios (95% CIs) of diabetes were 10.55 (2.95-37.67) for pharynx cancer, 5.78 (1.72-19.40) for small intestine cancer, 2.37 (1.14-4.91) for liver cancer and 0.48 (0.35-0.67) for prostate cancer. In people with diabetes, diabetes duration was dose-dependently associated with cancer risk. In conditional logistic regression analysis of 176 prostate cancer-discordant twin pairs, the association between midlife diabetes and prostate cancer in later life became stronger. Midlife diabetes increases the risk of pharynx, small intestine and liver cancers, but reduces prostate cancer risk in late life. Genetic and early-life environmental factors may partially contribute to the diabetes-prostate cancer association.

Obesity, Diabetes and Gastrointestinal Malignancy: The role of Metformin and other Anti-diabetic Therapy

The association between Diabetes and cancer has been known for decades with obesity and insulin resistance being postulated as the main underlying risk factors for both disorders. With rise of the epidemic of obesity in the USA and around the globe, there has been a rise in diabetes that is currently reaching epidemic proportions. Diabetes is known to be associated with increased risk of several types of malignancy including breast, cervical, pancreatic and colon cancer. In this review, we discuss the epidemic of obesity and its consequential epidemic of diabetes highlighting the pathophysiologic mechanisms of increased cancer in the diabetic population. We will then discuss the role of insulin therapy as well as, other antidiabetic medications, particularly metformin that has been to be associated with lower risk as well as better survival with GI malignancies based on several studies including a study that was recently published by our group.

Metformin use and its effect on gastric cancer in patients with type 2 diabetes: A systematic review of observational studies

Increasing evidence suggests that metformin use is associated with a decreased risk of cancer. The traditional therapies for gastric cancer (GC) are gastrectomy and chemoradiotherapy; however, these therapies may cause certain adverse effects, which affect a patient's quality of life, and the overall survival rate is low. At present, little is known about whether the use of metformin decreases the risk of GC in patients with type 2 diabetes. Therefore, in the present study, a systematic review was performed to analyze the effect of metformin on GC. A literature search was conducted in PubMed, EMBASE, and the Cochrane Library databases for articles published up to June 30th, 2016. The studies that evaluated GC patients treated with metformin and compared them with GC patients treated with other antidiabetic drugs were reviewed. Eligible studies were evaluated using the Newcastle-Ottawa Scale. Adjusted hazard ratio and 95% confidence intervals were determined to evaluate the effect of metformin on GC. From the 422 articles evaluated, 5 studies involving a total of 1,804,479 patients met the inclusion criteria and were qualitatively analyzed. The quality of all selected articles was classified as moderate. These studies reported that the long-term use of metformin was associated with a lower risk of GC compared with the lack of use of metformin or the use of other hypoglycemic drugs. In GC patients with diabetes who were subjected to gastrectomy, the cumulative use of metformin reduced the rates of disease recurrence and of all-cause and cancer-specific mortality. Despite the limited number of studies on this subject, currently available evidence indicates that metformin is associated with a decreased risk of GC and improves survival in patients with type 2 diabetes. However, more well-designed trials are required to elucidate this association.

Male non-insulin users with type 2 diabetes mellitus are predisposed to gastric corpus-predominant inflammation after H. pylori infection

BACKGROUND

Both H. pylori infection and diabetes increase the risk of gastric cancer. This study investigated whether patients with type 2 diabetes mellitus (T2DM) and H. pylori infection had more severe corpus gastric inflammation and higher prevalence of precancerous lesions than non-diabetic controls.

METHODS

A total of 797 patients with type 2 diabetes mellitus were screened for H. pylori, of whom 264 had H. pylori infection. Of these patients, 129 received esophagogastroduodenoscopy to obtain topographic gastric specimens for gastric histology according to the modified Updated Sydney System, corpus-predominant gastritis index (CGI), Operative Link on Gastritis Assessment, and Operative Link on Gastric Intestinal Metaplasia Assessment. Non-diabetic dyspeptic patients who had H. pylori infection confirmed by esophagogastroduodenoscopy were enrolled as controls.

RESULTS

The male as well as total T2DM patients had higher acute/chronic inflammatory and lymphoid follicle scores in the corpus than non-diabetic controls (p < 0.05). In contrast, the female T2DM patients had higher chronic inflammatory scores in the antrum than the controls (p < 0.05). In T2DM patients, the males had significantly higher rates of CGI than the females (p < 0.05). Multivariate logistic regression analysis showed that male patients (odds ratio: 2.28, 95% confidence interval: 1.11-4.69, p = 0.025) and non-insulin users (odds ratio: 0.33, 95% confidence interval: 0.15-0.74, p = 0.007) were independent factors for the presence of CGI in the H. pylori-infected patients with type 2 diabetes mellitus.

CONCLUSIONS

Patients with type 2 diabetes mellitus and H. pylori infection had more severe corpus gastric inflammation than non-diabetic controls. Moreover, male gender and non-insulin users of T2DM patients were predisposed to have corpus-predominant gastritis after H. pylori infection.

TRIAL REGISTRATION

ClinicalTrial: NCT02466919 , retrospectively registered may 17, 2015.

Association between alcohol consumption and the risk of gastric cancer: a meta-analysis of prospective cohort studies

Alcohol consumption is inconsistently associated with the risk of gastric cancer morbidity and mortality. The aim of this study was to systematically evaluate the association between alcohol consumption on gastric cancer risk. The PubMed, Embase, and Cochrane Library databases were searched from inception through April 2017. Prospective cohort studies evaluating the association between alcohol consumption and risk of gastric cancer which report its effect estimates with 95% confidence intervals (CIs) were included. The results summary was performed using the random-effect model. Twenty-two cohort studies involving 22,545 cases of gastric cancer and 5,820,431 participants were identified and included in our data analysis. Overall, drinking had little or no effect on gastric cancer as compared with non-drinkers. Furthermore, light and moderate alcohol consumption had no significant effect on gastric cancer risk when compared with non-drinkers. However, heavy alcohol consumption was associated with a greater risk of gastric cancer when compared with non-drinkers. The findings of the subgroup analyses indicated that light alcohol consumption was associated with a lower risk of gastric cancer in women, while heavy alcohol consumption was associated with an increased risk of gastric cancer regardless of country, gender, whether the study reported gastric cancer incidence, or whether the study adjusted for body mass index, educational attainment, or physical activity. The findings of this study suggest that light alcohol consumption might play a protective effect on gastric cancer in women, while heavy alcohol consumption is associated with a significantly increased risk of gastric cancer in all subgroups.

Diabetic biomarkers and the risk of proximal or distal gastric cancer

BACKGROUND AND AIM

The role of diabetes mellitus as a risk factor for gastric cancer has been controversial. We studied the association between diabetic biomarkers and the risk of gastric cancer and whether these associations depend on cancer location.

METHODS

In this retrospective cohort study with subjects with negative initial esophagogastroduodenoscopy findings (n = 23 218) during a routine health checkup, we measured fasting glucose and insulin levels, calculated the homeostatic model assessment insulin resistance (HOMA-IR) values, and analyzed the risk of gastric cancer in relation to diabetic biomarker tertiles and the presence of diabetes mellitus.

RESULTS

The incidence rate of gastric cancer was 9.7 per 10 000 person-years during the mean 6.8-year follow up. Patients with diabetes, higher fasting glucose levels, or higher HOMA-IR levels were older; men, current smokers, and heavy alcohol consumers represented larger proportions of these groups. They also had high body mass index and hemoglobin A1c more often. In the multivariate-adjusted Cox regression analyses, the incidence of gastric cancer was not significantly associated with diabetes mellitus or higher diabetic biomarker levels. Compared with normal glucose levels, lower glucose levels were significantly associated with an increased risk of distal gastric cancer. The hazard ratio for fasting glucose level tertile 1 was 2.39 (95% confidence interval, 1.48-3.85) (reference, tertile 2). Lower glucose levels were not associated with a risk of proximal gastric cancer, compared with a normal glucose level.

CONCLUSIONS

Our findings suggest that fasting glucose levels have a different effect on distal and proximal gastric cancers.

Synergistic Benefit of Statin and Metformin in Gastrointestinal Malignancies

OBJECTIVES

To evaluate whether statin use influences gastrointestinal cancer prognosis in patients with diabetes mellitus (DM).

METHODS

We reviewed all DM patients diagnosed at Roswell Park Cancer Institute with emergent gastrointestinal malignancy (January 2003 to December 2010) (N = 222). Baseline demographic, clinical history, and cancer outcomes were documented. Overall survival (OS) and disease-free survival (DFS) comparisons across various treatment groups were assessed by Kaplan-Meier and Cox proportional hazards.

RESULTS

Use of statin, alone or in combination, was associated with improved OS and DFS (hazard ratio [HR] = 0.65, P = .06; HR = 0.60, P < .02). We report similar OS and DFS advantage among users of mono- or combined metformin therapy (HR = 0.55, P < .01; HR = 0.63, P < .02). Concomitant use of metformin and statin provided a synergistic OS and DFS benefit (HR = 0.42, P < .01; HR = 0.44, P < .01). Despite significant tobacco and alcohol use history, patients with upper gastrointestinal cancers derived enhanced cancer outcomes from this combination (HR = 0.34, P < .01; HR = 0.43, P < .02), while receiving a statin without metformin or metformin without a statin did not provide significant cancer-related benefits.

CONCLUSION

Use of statin and metformin provides a synergistic improvement in gastrointestinal malignancies outcomes.

Time-Dependent Risk of Cancer After a Diabetes Diagnosis in a Cohort of 2.3 Million Adults

Using a time-dependent approach, we investigated all-site and site-specific cancer incidence in a large population stratified by diabetes status. The study analyzed a closed cohort comprised of Israelis aged 21-89 years, enrolled in a health fund, and followed from 2002 to 2012. Adjusting for age, ethnicity, and socioeconomic status, we calculated hazard ratios for cancer incidence using Cox regression separately for participants with prevalent and incident diabetes; the latter was further divided by time since diabetes diagnosis. Of the 2,186,196 individuals included in the analysis, 159,104 were classified as having prevalent diabetes, 408,243 as having incident diabetes, and 1,618,849 as free of diabetes. In both men and women, diabetes posed an increased risk of cancers of the liver, pancreas, gallbladder, endometrium, stomach, kidney, brain (benign), brain (malignant), colon/rectum, lung (all, adenocarcinoma, and squamous cell carcinoma), ovary, and bladder, as well as leukemia, multiple myeloma, non-Hodgkin lymphoma, and breast cancer in postmenopausal women. No excess risk was observed for breast cancer in premenopausal women or for thyroid cancer. Diabetes was associated with a reduced risk of prostate cancer. Hazard ratios for all-site and site-specific cancers were particularly elevated during the first year following diabetes diagnosis. The findings of this large study with a time-dependent approach are consistent with those of previous studies that have observed associations between diabetes and cancer incidence.

Gastric atrophy and xanthelasma are markers for predicting the development of early gastric cancer

BACKGROUND

The significance of gastric xanthelasma in relation to gastric cancer still remains unclear. We investigated whether gastric xanthelasma would be a useful marker for predicting the development of early gastric cancer.

METHODS

A total of 1823 patients who underwent a medical health checkup were enrolled. We examined the relationship between gastric xanthelasma and various clinical features, and in an endoscopic follow-up study investigated whether the presence of gastric xanthelasma was predictive of the development of early gastric cancer.

RESULTS

In the initial endoscopic examination, gastric xanthelasma was detected in 107 (5.9 %) of the 1823 patients. The presence of gastric xanthelasma was significantly associated with age ≥65 years, male gender, open-type atrophy, and the presence of diabetes mellitus (DM) (p < 0.0001, p < 0.0001, p < 0.0001, and p < 0.0001, respectively). During the endoscopic follow-up period, early gastric cancer was found in 29 (1.6 %) of the 1823 patients. Gastric cancer occurred in 15 (14.0 %) of 107 patients with gastric xanthelasma, whereas it occurred in 14 (0.8 %) of 1716 patients without (p < 0.0001). Multivariate analysis revealed that open-type atrophy and gastric xanthelasma were independently related to the development of gastric cancer (odds ratio 7.19 [2.50-20.83]; p = 0.0003 and 5.85 [2.67-12.82]; p < 0.0001, respectively). The presence of gastric xanthelasma was significantly predictive of gastric cancer development even in the selected high-risk groups with open-type atrophy or DM (p < 0.0001 or p < 0.0001, respectively).

CONCLUSIONS

Gastric xanthelasma is a useful marker for predicting the development of gastric cancer.

New-onset type 2 diabetes, elevated HbA1c, anti-diabetic medications, and risk of pancreatic cancer

Background:

Associations between type 2 diabetes, anti-diabetic medications and pancreatic cancer are controversial. This study aims to clarify such associations with new-onset type 2 diabetes and repeated measurements of glycated haemoglobin (HbA1c) levels.

Methods:

A nested case–control study was initiated from the Health Improvement Network (THIN) in UK from 1996 to 2010. Information of pancreatic cancer cases was retrieved electronically from the medical records and manually validated. Control subjects were randomly selected and frequency-matched to the cases on sex, age, and calendar years. Multivariable unconditional logistic regression was performed to estimate odds ratios (OR) and 95% confidence intervals (CI), and adjusted for potential confounders.

Results:

Among 1 574 768 person-years of follow-up, 529 pancreatic cancer cases and 5000 controls were identified. Type 2 diabetes, or changed HbA1c levels (rather than HbA1c levels at diabetes diagnosis) in diabetes patients (⩾4 mmol mol⁻¹ compared with <0 mmol mol⁻¹) were followed by an increased OR of pancreatic cancer (OR, 2.16, 95% CI 1.72–2.72 and OR, 5.06, 95% CI 1.52–16.87, respectively). Among the anti-diabetic medications in diabetes patients, the OR for insulin users was 25.57 (95% CI 11.55–56.60), sulphonylureas 2.22 (95% CI 1.13, 4.40), and metformin users 1.46 (95% CI 0.85–2.52), compared with no use of any anti-diabetic medications.

Conclusions:

New-onset type 2 diabetes and, particularly, diabetes with rising HbA1c seem to be independent risk factors for pancreatic cancer. The relation between different anti-diabetic medications and pancreatic cancer seems to vary in strength, with the highest risk among users of insulin.

Association of diabetes and cancer mortality in American Indians: the Strong Heart Study

PURPOSE

The metabolic abnormalities that accompany diabetes mellitus are associated with an increased risk of many cancers. These associations, however, have not been well studied in American Indian populations, which experience a high prevalence of diabetes. The Strong Heart Study is a population-based, prospective cohort study with extensive characterization of diabetes status.

METHODS

Among a total cohort of 4,419 participants who were followed for up to 20 years, 430 cancer deaths were identified.

RESULTS

After adjusting for sex, age, education, smoking status, drinking status, and body mass index, participants with diabetes at baseline showed an increased risk of gastric (HR 4.09; 95% CI 1.42-11.79), hepatocellular (HR 2.94; 95% CI 1.17-7.40), and prostate cancer mortality (HR 3.10; 95% CI 1.22-7.94). Further adjustment for arsenic exposure showed a significantly increased risk of all-cause cancer mortality with diabetes (HR 1.27; 95% CI 1.03-1.58). Insulin resistance among participants without diabetes at baseline was associated with hepatocellular cancer mortality (HR 4.70; 95% CI 1.55-14.26).

CONCLUSIONS

Diabetes mellitus, and/or insulin resistance among those without diabetes, is a risk factor for gastric, hepatocellular, and prostate cancer in these American Indian communities, although relatively small sample size suggests cautious interpretation. Additional research is needed to evaluate the role of diabetes and obesity on cancer incidence in American Indian communities as well as the importance of diabetes prevention and control in reducing the burden of cancer incidence and mortality in the study population.

Gastric cancer diagnosed after Helicobacter pylori eradication in diabetes mellitus patients

Background

Helicobacter pylori infection is the most important risk factor for gastric cancer, for which eradication therapy is commonly performed. However, gastric cancer is sometimes discovered after successful eradication of H. pylori. Much evidence indicates that diabetes mellitus (DM) is a risk factor for gastric cancer. The incidence and characteristics of gastric cancer diagnosed after H. pylori eradication in DM patients remain to be determined.

Methods

We followed the clinical course of patients who underwent H. pylori eradication therapy at our institution. Endoscopy was performed before and after eradication. We compared the incidence and clinical characteristics of gastric cancer arising in DM and non-DM patients.

Results

In total, 965 patients who underwent successful eradication (518 DM and 447 non-DM patients) were followed-up for an average of 4.5 years. During the follow-up period, 21 gastric cancers were diagnosed (12 in DM patients and 9 in non-DM patients). The incidence of gastric cancer after eradication was not significantly different between DM and non-DM patients (0.485 and 0.482 %/year, respectively). There was no significant difference in the pathology, diameter, depth, location, or treatment of gastric cancer between patients with and without DM.

Conclusion

The incidence and characteristics of gastric cancer occurring after H. pylori eradication were comparable between DM and non-DM patients.

Hyperglycemia Promotes Human Gastric Carcinoma Progression via Aquaporin 3

BACKGROUND

Hyperglycemia plays an important role in the development of gastric carcinoma (GC). Aquaporin 3 (AQP3) is overexpressed in GC and involved in carcinogenesis and progression of GC. Hyperglycemia promotes AQP3 expression in human peritoneal mesothelial cells.

AIMS

To investigate whether hyperglycemia promotes progression of GC via AQP3.

METHODS

We enrolled 978 patients with GC and evaluated the correlation between preoperative fasting plasma glucose and clinicopathological features. AQP3 was detected by immunohistochemistry in human GC specimens. Western blotting and real-time quantitative polymerase chain reaction evaluated changes in AQP3 expression in human GC MGC803 and SGC7901 cells after co-culture with high glucose. Transwell migration and Cell Counting Kit-8 assays were used to determine migration and proliferation of GC cells.

RESULTS

Hyperglycemia (fasting plasma glucose ≥6.1 mM) correlated with tumor size, location, and pTNM stage. AQP3 expression in tumor tissue was associated with fasting plasma glucose levels. High glucose concentration upregulated AQP3 expression in a dose- and time-dependent manner. High glucose concentration promoted GC cell migration markedly, and AQP3 knockdown with siRNA could abolish the increase in cell migration. However, high glucose concentration inhibited cell proliferation, and AQP3 knockdown significantly enhanced the inhibitory effect of high glucose. The ERK and PI3K/AKT signaling pathways were involved in high glucose regulation of AQP3 in human GC cells.

CONCLUSION

Hyperglycemia promotes GC progress via AQP3. This improves our understanding of the mechanism of hyperglycemia-induced carcinogenesis and provides a potential therapeutic strategy for GC.

Cancer risk among patients with type 2 diabetes mellitus: a population-based prospective study in China

Evidence indicates an increased cancer risk among type 2 diabetes mellitus (T2DM) patients, yet studies in mainland China are scarce. Based on Diabetes Surveillance System linking to Cancer Surveillance System of Zhejiang Province in China, we explored the cancer risk among T2DM patients. Totally, 327,268 T2DM patients were identified and followed from January 1, 2007 to December 31, 2013. Standardized incidence ratios (SIRs) with 95% confidence intervals (CIs) were reported. Overall cancer risk was found significantly increased with an SIR of 1.15 (95% CI 1.12-1.19) and 1.25 (95% CI 1.21-1.30) in males and females, respectively. Regarding specific cancer sites, risks of liver, colon, rectum, pancreas, and kidney were significantly increased with SIRs of 1.26 (95% CI 1.16-1.36), 1.47 (95% CI 1.29-1.67), 1.25 (95% CI 1.09-1.43), 2.81 (95% CI 2.50-3.16) and 1.61 (95% CI 1.28-2.03) in males, 1.53 (95% CI 1.35-1.73), 1.33 (95% CI 1.15-1.54), 1.29 (95% CI 1.10-1.51), 3.62 (95% CI 3.20-4.09) and 1.71 (95% CI 1.28-2.29) in females, respectively. A significant increased SIR was noted for prostate (1.80, 95% CI 1.58-2.06). Significant increased SIRs for lung (1.32, 95% CI 1.20-1.44) and stomach (1.16, 95% CI 1.03-1.30) were observed in females. We suggested an increased cancer risk among T2DM patients.

Hepatitis B virus infection is associated with gastric cancer in China: an endemic area of both diseases

Background:

Hepatitis B virus (HBV) infection was demonstrated to be a risk factor of several cancers of the digestive system. In addition, liver cirrhosis, which could possibly result from chronic HBV infection, was associated with a higher risk of gastric cancer. However, the association of HBV infection and gastric cancer has not been investigated.

Methods:

A retrospective case–control study with 580 cases and 580 controls matched for age, sex and year of diagnosis was conducted. The associations between gastric cancer and HBV infection were explored with univariate and multivariate unconditional logistic regression analysis.

Results:

Hepatitis B surface antigen (HBsAg) was positively associated with gastric cancer (AOR (95% CI): 1.49 (1.06–2.10)). This association remained significant in patients without family history of gastric cancer (AOR (95% CI): (1.06–2.11)). For HBsAg-negative population, being anti-HBc positive/anti-HBs negative, which possibly indicated occult HBV infection, was also found to have some associations with gastric cancer. In addition, some synergistic effects between HBV infection and blood type A in gastric cancer were identified.

Conclusions:

The HBV infection was positively related with gastric cancer, especially for patients without family history of gastric cancer. Further prospective studies are warranted to confirm this relationship.

Glucagon phosphorylates serine 552 of β-catenin leading to increased expression of cyclin D1 and c-Myc in the isolated rat liver

In the last 20 years the prevalence of metabolic disorders, in particular type 2 diabetes (T2D), has more than doubled. Recently, a strong link between T2D and cancer, in particularly liver cancer has been reported. However, the mechanism connecting the development of type 2 diabetes and cancer remains unknown. One of the biggest drivers of liver cancer is alterations in the Wnt/β-catenin pathway. In this study, we aimed to identify the effect of glucagon on β-catenin in the isolated rat liver. We found glucagon, which is substantially raised in patients with T2D, rapidly phosphorylates β-catenin on serine 552 that is associated with increased expression of genes cyclin D1 (CCND1) and c-Myc (MYC), which are known to be involved in liver cancer. This finding may explain the increased risk of liver cancer in people with T2D.

Diabetes and cancer: A critical appraisal of the pathogenetic and therapeutic links

Diabetes and cancer represent two common, multifactorial, chronic and potentially fatal diseases, not infrequently co-diagnosed in the same patient. Epidemiological data demonstrate significant increases of the cancer incidence in patients with obesity and diabetes, which is more evident for certain site-specific cancers. Although there is increasing evidence that strongly indicates an augmented risk of cancer in diabetic patients, several confounding factors complicate the ability to precisely assess the risk. Mainly in insulin-resistant states (such as in type 2 diabetes mellitus and in metabolic syndrome), direct associations between obesity-related hyperinsulinemia and increasing circulating insulin-like growth factor-1 (IGF-1) levels have been implicated as key factors in the mechanisms involved in carcinogenesis. Whilst anti-diabetic drugs can increase the cancer risk, anti-proliferative drugs may cause diabetes or aggravate pre-existing diabetes. Additionally, an increasing number of targeted anti-cancer therapies may interfere with the pathways shared by IGF-1 and insulin receptors, showing a adverse effect on glucose metabolism through various mechanisms. Although there is a requirement for large-scale randomized evidence, the present review summarizes the majority of the epidemiological association studies between diabetes and various types of cancer, discussing the pathophysiological mechanisms that may be involved in promoting carcinogenesis in diabetes and the potential impact of different anti-diabetic therapies on cancer risk.

Impact of diabetes mellitus on the prognosis of patients with hepatocellular carcinoma after curative hepatectomy

BACKGROUND

The influence of diabetes mellitus (DM) on the prognosis of patients with hepatocellular carcinoma (HCC) remains controversial. Here we investigated the impact of DM on the prognosis of such patients after curative hepatectomy.

METHODS

A consecutive cohort of 505 patients with HCC (134 with DM, 371 without) underwent curative hepatectomy were retrospectively evaluated. Postoperative morbidity and mortality, overall survival (OS) and disease-free survival (DFS) were compared between patients with or without DM. Independent prognostic predictors were identified using the Cox proportional hazards model.

RESULTS

Patients with or without DM showed similar morbidity and 30- and 90- day mortality after curative hepatectomy (all P>0.05), as well as similar DFS at 1, 3, 5 years (P = 0.781). However, the group of patients with DM showed significantly lower OS at 1, 3, 5 years than the group without DM (P = 0.038). Similar results were obtained in the propensity-matched cohort. Cox multivariate analysis identified DM as an independent predictor of poor OS, but not of poor DFS. We repeat compared OS and DFS for DM and non-DM subgroups defined according to the presence or absence of hepatitis B virus infection and cirrhosis. Similar results were obtained in all subgroups except the non-cirrhotic subgroup which showed patients with and without DM had similar OS.

CONCLUSIONS

DM does not significantly affect the postoperative morbidity or mortality or the DFS of patients with HCC after curative hepatectomy. It is, however, associated with significantly lower OS, especially in patients with cirrhosis.

Antihyperglycaemic therapies and cancer risk

AIMS

This review is aimed at highlighting the potential mitogenic/tumour growth-promoting or antimitogenic/tumour growth-inhibiting effects of the main antihyperglycaemic drug classes.

METHODS

We review and discuss the most current studies evaluating the association between antidiabetic medications used in clinical practice and malignancies as described so far.

RESULTS

Metformin seems to be the only antidiabetic drug to exert protective effects both on monotherapy and also when combined with other oral antidiabetic drugs or insulins in several site-specific cancers. In contrast, several other drug classes may increase cancer risk. Some reason for concern remains regarding sulphonylureas and also the incretin-based therapies regarding pancreas and thyroid cancers and the sodium glucose cotransporter-2 inhibitors as well as pioglitazone regarding bladder cancer. The majority of meta-analyses suggest that there is no evidence for a causal relationship between insulin glargine and elevated cancer risk, although the studies have been controversially discussed. For α-glucosidase inhibitors and glinides, neutral or only few data upon cancer risk exist.

CONCLUSION

Although the molecular mechanisms are not fully understood, a potential risk of mitogenicity and tumour growth promotion cannot be excluded in case of several antidiabetic drug classes. However, more large-scale, randomized, well-designed clinical studies with especially long follow-up time periods are needed to get reliable answers to these safety issues.

Coffee consumption and risk of gastric cancer: a large updated meta-analysis of prospective studies

The potential role of coffee consumption in the development of various types of cancer has been extensively investigated in epidemiologic studies. How coffee consumption may modulate risk of gastric cancer, however, remains a subject open for investigation. To better quantify this relation, we quantitatively summarized evidence from prospective studies. Eligible studies were identified on PubMed databases. The summary risk estimates were obtained using the random-effects model. Subgroup, sensitivity and dose-response analyses were conducted. The present meta-analysis included 12 prospective cohort studies. A pooled analysis of these studies suggested that coffee consumption (highest vs. lowest consumption) was not associated with risk of gastric cancer (RR = 1.12, 95% CI = 0.93–1.36). In the subgroup analysis, significant increased risk was detected in the U.S. studies (RR = 1.36, 95% CI = 1.06–1.74) and in the studies with <10 years of follow-up (RR = 1.24, 95% CI = 1.00–1.54), and the greatest increase in risk was observed in those studies without adjustment for smoking (RR = 1.48, 95% CI = 1.13–1.93). There was some evidence of publication bias (P for Egger’s test = 0.03). Cumulative evidence from prospective studies suggests that coffee consumption is not associated with risk of gastric cancer. The observed positive results may be confounded by smoking and need further investigation.