Type 2 diabetes mellitus and risk of gallbladder cancer: a systematic review and meta-analysis of observational studies

The inverse association between fasting blood glucose and the occurrence of gallbladder cancer in type 2 diabetes mellitus patients: a case-control study

OBJECTIVE

This study aimed to explore the correlation between diabetes mellitus (DM) and gallbladder cancer (GBC) in an epidemiological setting.

METHODS

The study summarized the clinical and laboratory data of 2210 GBC Chinese patients in the authors' hospital. A total of 17 influencing factors for GBC, including gender, body mass index (BMI), fasting blood glucose (FBG), fasting insulin (FINS), the homeostasis model assessment of insulin resistance (HOMA-IR), retinol-binding protein 4 (RBP4), and lipid indexes were analyzed using unconditional logistic regression analysis.

RESULTS

Based on the results of univariate logistic regression, the risk of GBC was significantly and positively correlated with serum triglyceride, low-density lipoprotein, FINS, HOMA-IR, being female, BMI, DM, non-alcoholic fatty liver disease, and gallbladder stone disease (GSD), and significantly negatively correlated with high-density lipoprotein and FBG concentrations in serum, as well as hypertension. According to multivariate analysis, FINS was significantly positively associated with GBC risk, while DM showed an insignificant negative association; FBG was also not important. The most significant independent factor of GBC risk in patients with DM was HOMA-IR. Fasting blood glucose levels showed a significant negative relationship with GBC in patients with DM. In addition, this study indicated a significantly negative association between serum RBP levels and GBC.

CONCLUSIONS

The findings of the current study revealed that the efficient treatment of insulin resistance is an important approach for decreasing GBC risk, as opposed to lowering blood sugar only, particularly in patients with DM. Interestingly, FBG may have had an inverse association with the development of GBC in patients with type 2 DM. Of note, the study found that a dramatic initial drop in RBP may help predict the occurrence of GBC.

[Type-2-diabetes and gastrointestinal cancer screening]

More than 8000000 Germans suffer from diabetes. People with type-2-diabetes (T2D) are at increased risk of gastrointestinal adenocarcinomas. They often develop cancer at younger age and their tumor-specific 5-year-survival is generally shorter. Cancer has become the leading cause of death of T2D-patients. Both chronic hyperglycemia and insulin resistance can stimulate gastrointestinal (GI) tumor growth. T2D can cause colorectal, pancreatic, hepatocellular, biliary and gastric cancer as well as esophageal adenocarcinoma. Both low-risk lifestyle and gastrointestinal cancer screening are effective and reduce GI cancer risk and GI cancer mortality of T2D-patients.

Effects of Metformin on Risk and Prognosis of Biliary Tract Cancer: A Systematic Review and Meta-Analysis

Background and Objectives: Metformin has been found to potentially reduce the risk and improve the prognosis of a variety of tumors, but these findings remain controversial in biliary tract cancer (BTC). Therefore, this systematic review and meta-analysis was conducted to investigate the association between metformin and BTC. Materials and Methods: Two independent researchers comprehensively searched PubMed, Embase, the Cochrane Library, and Web of Science for eligible studies published from their inception to 31 March 2022. Comparisons of risk, overall survival (OS), and disease-free survival (DFS) for patients with BTC were selected as the endpoints of interest and pooled by random or fixed-effects models. Results: Eleven studies with a total of 24,788,738 participants were eligible for this analysis. The overall pooled effects showed no significant differences in biliary tract cancer risk (hazard ratio (HR) = 0.82, 95% confidence interval (CI): 0.50-1.35, p = 0.436), OS (HR = 0.88, 95% CI: 0.74-1.04, p = 0.135), or DFS (HR = 1.03, 95% CI: 0.79-1.34, p = 0.829) between metformin users and non-users. When restricting participants to those with diabetes, a similar negative result was found, demonstrating that metformin use was not significantly associated with a lower risk of developing BTC compared with a lack of metformin use (HR = 0.65, 95% CI: 0.39-1.07, p = 0.089); notably, the included studies exhibited significant heterogeneity in the selection of participants and the definition of metformin users. Conclusions: Metformin may not be able to reduce the risk of BTC and improve prognosis in certain populations. Based on the limited quantity and quality of the included studies, the present results should be interpreted within their limitations, and further studies are warranted to determine the optimal timing, dose, duration, and scenario of metformin administration.

Receptor of advanced glycation end-products axis and gallbladder cancer: A forgotten connection that we should reconsider

Compelling evidence derived from clinical and experimental research has demonstrated the crucial contribution of chronic inflammation in the development of neoplasms, including gallbladder cancer. In this regard, data derived from clinical and experimental studies have demonstrated that the receptor of advanced glycation end-products (RAGE)/AGEs axis plays an important role in the onset of a crucial and long-lasting inflammatory milieu, thus supporting tumor growth and development. AGEs are formed in biological systems or foods, and food-derived AGEs, also known as dietary AGEs are known to contribute to the systemic pool of AGEs. Once they bind to RAGE, the activation of multiple and crucial signaling pathways are triggered, thus favoring the secretion of several proinflammatory cytokines also involved in the promotion of gallbladder cancer invasion and migration. In the present review, we aimed to highlight the relevance of the association between high dietary AGEs intakes and high risk for gallbladder cancer, and emerging data supporting that dietary intervention to reduce gallbladder cancer risk is a very attractive approach that deserves much more research efforts.

Gastrointestinal and Liver Complications in Patients with Diabetes Mellitus-A Review of the Literature

The number of diabetes mellitus patients has increased over the last few years in developing countries, along with obesity and sedentary lifestyle. Besides macroangiopathy and microangiopathy, damage to the nerve fibers of the peripheral nervous system is the most common chronic complication of diabetes. Digestive complications in diabetic patients represent a consequence of diabetic autonomic neuropathy involving the gastrointestinal tract, but unfortunately not always evaluated by diabetologists. Aside from the complications encountered in the digestive tract, patients with diabetes mellitus are prone to developing liver diseases. This review will describe the prevalence of these complications, the modality of diagnosis, and therapeutical solutions in order to reduce the risk of progression of these complications in diabetic subjects.

The role of diet and nutrition related indicators in biliary diseases: an umbrella review of systematic review and meta-analysis

BACKGROUND

Diet and nutrition, as a modifiable risk factor, have been demonstrated to play a significant role in the etiology of biliary diseases, whereas few comprehensive studies have been able to evaluate the strength and quality of these evidence. This umbrella review aims to evaluate the evidence pertaining risk factors for biliary diseases in terms of diet and nutrition-related indicators.

METHODS

An umbrella review method was adopted: evidence from observational studies up to 22 November 2021 were identified using PubMed, Web of Science, the Cochrane database, as well as manual screening. Eligible systematic reviews and meta-analyses were screened according to inclusion and exclusion criteria. The inclusion criteria were: (1) meta analysis or systematic review; (2) The theme of the study is the relationship between diet or nutrition and biliary tract diseases; (3) Summarized and reported OR, RR or HR values and corresponding 95% CI; (4) No restrictions on the use of participants and languages; (5) Only extract the data of biliary tract diseases from multiple health outcomes; (6) Only the most recent studies on the same subject were included. This study had been registered at PROSPERO (CRD42021293908). For each eligible systematic review and meta-analysis, we extracted the data of general characteristics and the main findings. The methodological quality of the meta-analyses included in our study were assessed by AMSTAR2 and the quality of evidence was evaluated by the GRADE.

RESULTS

A total of 323 articles were searched, among which 24 articles with 83 unique outcomes were identified as eligible. 35 of these outcomes were downgraded in GRADE evaluation as they reported heterogeneity. In short, among 83 unique outcomes, 5 were rated as moderate, 16 as low, and the rest as very low. For the prevention of biliary tract diseases, emphasis should be placed on appropriately increasing the intake of fruits, vegetables, coffee and tea, and reducing the intake of alcohol, raw fish and foods with high nitrate. Meanwhile, weight, blood sugar and lipid levels should be controlled, and diabetes should be actively prevented and treated. Drinking is not recommended to prevent gallstones, although studies have shown that it may reduce the risk of cholecystolithiasis.

CONCLUSIONS

Our study summarizes the current multifaceted evidence on the relationship between dietary and nutritional indicators and biliary diseases, but the quality of all evidence was not high. Evidence from additional high-quality prospective studies are needed in the future.

A nomogram-based model and ultrasonic radiomic features for gallbladder polyp classification

BACKGROUND AND AIM

Gallbladder polyps (GBPs) are relatively common. Many studies have attempted to distinguish between benign and neoplastic GBPs to identify early-stage gallbladder carcinoma. We have established an accurate neoplastic predictive model and evaluated the effectiveness of radiomics in predicting malignancy in patients with GBPs.

METHODS

A total of 503 patients confirmed through postoperative pathology were included in this retrospective study. Clinical information and ultrasonographic findings were retrospectively analyzed. The model was constructed from independent risk factors using Spearman correlation and logistic regression analysis of a training cohort of 250 GBP patients, and its efficacy was verified using an internal validation group of 253 consecutive patients through the receiver operating characteristic curve (ROC). The area of GBPs was delimited manually, and the texture features of ultrasound images were analyzed using correlation and ROC analysis.

RESULTS

Independent predictors, including age, gallstones, carcinoembryonic antigen, polyp size, and sessile shape, were incorporated into the nomogram model for the neoplastic potential of GBPs. Compared with other proposed prediction methods, the established nomogram model showed good discrimination ability in the training group (area under the curve [AUC]: 0.865) and validation group (AUC: 0.845). Regarding ultrasonic radiomics, the minimum caliper diameter was identified as the only independent predictor (AUC: 0.841).

CONCLUSIONS

Our preoperative nomogram model can successfully evaluate the neoplastic potential of GBPs using simple clinical data, and our study verified the use of radiomics in GBP identification, which may be valuable for avoiding unnecessary surgery in patients.

Krebsrisiko bei Prädiabetes und Typ-2-Diabetes mellitus

Krebs ist nun die führende Todesursache bei Typ-2-Diabetes mellitus (T2D). Prädiabetes und T2D erhöhen das Risiko für bestimmte Tumoren. Zu den Prädiabetes- bzw. T2D-assoziierten Malignomen zählen gastrointestinale, gynäkologische, urologische und endokrine Karzinome aber auch Leukämien. Prädiabetes und T2D bedingen eine 1,2- bis 2,7-fach erhöhte Krebssterblichkeit. Zugrundeliegende Mechanismen der Assoziation zwischen T2D und Krebs beinhalten die chronische Hyperglykämie, einen chronischen systemischen Entzündungszustand, oxidativen Stress, Dyslipidämie, die Insulinresistenz sowie chronisch erhöhte Spiegel von insulin-like growth factor 1 (IGF-1) und von Insulin. Eine dauerhafte Gewichtsreduktion kann das Krebsrisiko adipöser T2D-Patienten signifikant senken. Ein gesunder Lebensstil und die regelmäßige Teilnahme an Vorsorgeuntersuchungen sind wichtig und können die Krebsmortalität von Diabetespatienten erheblich verringern.

A Nomogram-based Model to Predict Neoplastic Risk for Patients with Gallbladder Polyps

BACKGROUND AND AIMS

Gallbladder polyp (GBP) assessment aims to identify the early stages of gallbladder carcinoma. Many studies have analyzed the risk factors for malignant GBPs. In this retrospective study, we aimed to establish a more accurate predictive model for potential neoplastic polyps in patients with GBPs.

METHODS

We developed a nomogram-based model in a training cohort of 233 GBP patients. Clinical information, ultrasonographic findings, and blood test findings were analyzed. Mann-Whitney U test and multivariate logistic regression analyses were used to identify independent predictors and establish the nomogram model. An internal validation was conducted in 225 consecutive patients. Performance and clinical benefit of the model were evaluated using receiver operating characteristic curves and decision curve analysis (DCA), respectively.

RESULTS

Age, cholelithiasis, carcinoembryonic antigen, polyp size, and sessile shape were confirmed as independent predictors of GBP neoplastic potential in the training group. Compared with five other proposed prediction methods, the established nomogram model presented better discrimination of neoplastic GBPs in the training cohort (area under the curve [AUC]: 0.846) and the validation cohort (AUC: 0.835). DCA demonstrated that the greatest clinical benefit was provided by the nomogram compared with the other five methods.

CONCLUSIONS

Our developed preoperative nomogram model can successfully be used to evaluate the neoplastic potential of GBPs based on simple clinical variables that maybe useful for clinical decision-making.

Environmental and Lifestyle Risk Factors in the Carcinogenesis of Gallbladder Cancer

Gallbladder cancer (GBC) is an aggressive neoplasm that in an early stage is generally asymptomatic and, in most cases, is diagnosed in advanced stages with a very low life expectancy because there is no curative treatment. Therefore, understanding the early carcinogenic mechanisms of this pathology is crucial to proposing preventive strategies for this cancer. The main risk factor is the presence of gallstones, which are associated with some environmental factors such as a sedentary lifestyle and a high-fat diet. Other risk factors such as autoimmune disorders and bacterial, parasitic and fungal infections have also been described. All these factors can generate a long-term inflammatory state characterized by the persistent activation of the immune system, the frequent release of pro-inflammatory cytokines, and the constant production of reactive oxygen species that result in a chronic damage/repair cycle, subsequently inducing the loss of the normal architecture of the gallbladder mucosa that leads to the development of GBC. This review addresses how the different risk factors could promote a chronic inflammatory state essential to the development of gallbladder carcinogenesis, which will make it possible to define some strategies such as anti-inflammatory drugs or public health proposals in the prevention of GBC.

The association between diabetes and cancer in Mexico: Analysis using death certificate databases, 2009-2017

Context

Previous studies have shown that diabetes mellitus (DM) is a risk factor of some type-specific cancers. However, no data are available on the association between cancer and DM in Latin America.

Aims

The aim of this study is to determine which type-specific cancers are associated with DM using multiple cause of death data.

Settings and Design

Whole country of Mexico, cross-sectional design.

Materials and Methods

Analysis of all cancer deaths (2009-2017) using death certificate databases of Mexican adults aged ≥20 years.

Statistical Analysis Used

Multivariable logistic regression.

Results

There were 710,292 total cancer deaths. DM increased the risk of pancreatic (adjusted odds ratio [aOR] = 1.7), liver (aOR = 1.6), kidney (aOR = 1.4), gallbladder (aOR = 1.2) and endometrial (aOR = 1.1) cancers, all P < 0.05. Type 2 or unknown-type DM were associated with the same cancer types with little variation of estimates. Higher estimates were found in males than females (except for kidney cancer). Type 1 DM was associated with pancreatic cancer only (aOR = 1.9).

Conclusions

DM in Mexico is associated with gastrointestinal (pancreatic, liver, gallbladder), kidney and endometrial cancers. Dissemination of knowledge to both health-care workers and diabetics regarding potential cancer risks including adequate diet, regular exercise, weight reduction if obese/overweight, cessation of smoking, and good glucose control and medication compliance should be reinforced. Specific cancer preventative measures should be implemented for patients with DM.

Excess Body Weight and Gastrointestinal Cancer Risk

Background

Excess body weight (EBW), defined as a body mass index (BMI) ≥25 kg/m², has become the second most important as well as a potentially modifiable risk factor for cancer in many industrialized countries. The more excess weight people have, the higher the risk of certain cancers. Over the past several decades, EBW has been increasing globally not only among adults, but also among children and adolescents.

Summary

EBW is causally associated with colorectal, esophageal (adenocarcinoma), gastric (cardia), pancreatic, biliary and hepatocellular cancer. EBW when combined with tobacco smoking, risky alcohol use, or diabetes can act synergistically to cause gastrointestinal cancer. In recent years, more and more young adults (20-40 years old) were diagnosed with EBW-associated neoplasms. People with EBW should be encouraged to join cancer screening programs.

Key Messages

Keeping a healthy weight is a major public health concern and reduces the risk of cancer.

Worldwide distribution, associated factors, and trends of gallbladder cancer: A global country-level analysis

This study aimed to evaluate the global distribution, associated factors, and epidemiologic trends of gallbladder cancer (GBC) by country, sex, and age groups. The Global Cancer Observatory was interrogated for the disease burden of GBC using age-standardized rates (ASR). The prevalence of different potential risk factors for each country was extracted from Global Health Observatory and their associations with GBC incidence and mortality were examined by linear regression analysis using beta coefficients (β). The Cancer Incidence in Five Continents I-XI and the WHO Mortality database were searched and Average Annual Percent Change (AAPC) was generated from joinpoint regression analysis. The incidence (ASR = 2.3) and mortality (ASR = 1.7) of GBC varied globally in 2018 and were higher in more developed countries and among females. Countries with higher incidence had higher human development index (βmale = 0.37; βfemale = 0.27), gross domestic products (βmale = 0.13) and higher prevalence of current smoking (βfemale = 0.05), overweight (βmale = 0.02), obesity (βmale = 0.03), and hypercholesterolaemia (βmale = 0.07). Similar patterns of associations were also observed for mortality with an additional association found for diabetes (βfemale = 0.07). Although there was an overall decreasing trend in mortality, an increasing trend in incidence was observed among some populations, particularly in males (AAPCs, 8.97 to 1.92) and in younger individuals aged <50 years (AAPCs, 12.02 to 5.66). The incidence of GBC varied between countries and was related to differences in the prevalence of potential risk factors. There was an increasing incidence trend among males and younger individuals. More intensive lifestyle modifications and disease surveillance are recommended for these populations.

Comparing Age at Cancer Diagnosis between Hispanics and Non-Hispanic Whites in the United States

BACKGROUND

Population age structure may confound the comparison of age at cancer diagnosis across racial/ethnic groups. We compared age at cancer diagnosis for U.S. Hispanics, a population that is younger on average, and non-Hispanic whites (NHW), before and after adjustment for the age structure of the source population.

METHODS

We used Surveillance, Epidemiology, and End Results data from 18 U.S. regions in 2015 for 34 cancer sites to calculate crude and adjusted (using age- and sex-specific weights) mean ages at diagnosis. Differences in age at diagnosis comparing Hispanics to NHWs (δ) were assessed using independent sample t tests.

RESULTS

Crude mean ages at diagnosis were lower among Hispanic males and females for all sites combined and for most cancer sites. After age-adjustment, Hispanic (vs. NHW) males remained younger on average at diagnosis of chronic myeloid leukemia [δ = -6.1; 95% confidence interval (CI), -8.1 to -4.1 years], testicular cancer (δ =-4.7; 95% CI, -5.4 to -4.0), Kaposi sarcoma (δ =-3.6; 95% CI,-6.3 to -0.8), mesothelioma (δ =-3.0; 95% CI,-4.3 to -1.7), and anal cancer (δ =-2.4; 95% CI, -3.9 to -0.8), and older at diagnosis of gallbladder cancer (δ = +3.8; 95% CI, 1.8 to 5.7) and Hodgkin's lymphoma (δ = +7.5; 95% CI, 5.7 to 9.4), and Hispanic (vs. NHW) females remained younger at diagnosis of mesothelioma (δ = -3.7; 95% CI, -6.7 to -0.7) and gallbladder cancer (δ = -3.0; 95% CI, -4.3 to -1.7) and older at diagnosis of skin cancer (δ = +3.8; 95% CI, 3.1 to 4.5), cervical cancer (δ = +4.1; 95% CI, 3.3 to 4.8), and Hodgkin's lymphoma (δ = +7.0; 95% CI, 5.0 to 9.1).

CONCLUSIONS

On average, Hispanics are diagnosed with cancer at younger ages than NHWs; however, for many cancers these differences reflect the younger age structure in Hispanics.

IMPACT

Population age structure should be considered when comparing age at cancer diagnosis across racial/ethnic groups.

Type 2 Diabetes and Cancer: An Umbrella Review of Observational and Mendelian Randomization Studies

BACKGROUND

Type 2 diabetes mellitus (T2DM) has been associated with an increased risk of developing several common cancers, but it is unclear whether this association is causal. We aimed to summarize the evidence on T2DM and cancer and evaluate the validity of associations from both observational and Mendelian randomization (MR) studies.

METHODS

We performed an umbrella review of the evidence across meta-analyses of observational studies that examined associations of T2DM with risk of developing or dying from site-specific cancers, and MR studies that explored the potential causal association of T2DM and associated biomarkers with cancer risk.

RESULTS

We identified eligible observational meta-analyses that assessed associations between T2DM and cancer incidence for 18 cancer sites, cancer mortality for seven sites, and cancer incidence or mortality for four sites. Positive associations between T2DM and six cancers reached strong or highly suggestive evidence. We found eight MR studies assessing the association of genetically predicted T2DM and seven and eight studies assessing the association of genetically predicted fasting insulin or fasting glucose concentrations, respectively, upon site-specific cancers. Positive associations were found between genetically predicted T2DM and fasting insulin and risk of six cancers. There was no association between genetically predicted fasting plasma glucose and cancer except for squamous cell lung carcinoma.

CONCLUSIONS

We found robust observational evidence for the association between T2DM and colorectal, hepatocellular, gallbladder, breast, endometrial, and pancreatic cancers.

IMPACT

Potential causal associations were identified for genetically predicted T2DM and fasting insulin concentrations and risk of endometrial, pancreas, kidney, breast, lung, and cervical cancers.

Effect of metabolic syndrome components on the risk of malignancy in patients with gallbladder lesions

Background: Gallbladder lesions have become more common nowadays. But there is limited evidence-based guidance on surveillance of these patients for malignancy. Predicting malignancy could help clinicians better manage this condition and improve the prognosis. We evaluated the independent and joint effects of metabolic syndrome components on the risk of malignancy among patients with gallbladder lesions.

Methods: Using a multicenter database, consecutive patients with pathologically confirmed gallbladder lesions between 2012 and 2019 were identified. Univariate and multivariate logistic regression analyses were used to evaluate the effects of metabolic syndrome components (diabetes, hypertension, dyslipidemia and obesity) as additive or combined indicators for the risk of malignancy. Unadjusted and adjusted odds ratios were calculated.

Results: Of the 625 patients, 567 patients were identified with benign gallbladder lesions and 58 patients with gallbladder cancer (GBC). GBC group had less obesity but more dyslipidemia. Among all metabolic syndrome components, only dyslipidemia was significantly associated with GBC (odds ratio 2.674, 95% confidence interval 1.173-6.094). Dyslipidemia was an independent risk factor for malignancy (adjusted odds ratio 2.164, 95% confidence interval 1.165-4.021), regardless of whether the other risk factors and metabolic syndrome components were combined. Patients with decreased high-density lipoprotein had 3.035-fold higher risk of malignancy (adjusted odds ratio 3.035, 95% confidence interval 1.645-5.600).

Conclusions: Dyslipidemia is associated with a 2.674-fold increase in the risk of malignancy in patients with gallbladder lesions. Dyslipidemia is an independent risk factor for malignancy, regardless of the presence of the other risk factors and metabolic syndrome components.

Epidemiology of Gallbladder Cancer in Saudi Arabia

Background

Gallbladder cancer is generally rare but can be more common in some populations. The aim of this study was to present an analysis of gallbladder cancer epidemiology in Saudi Arabia.

Materials and Methods

A retrospective study of gallbladder cancer cases in Saudi Arabia from 2004 to 2015 was conducted. The gallbladder cancer data were accessed through the Saudi Cancer Registry (SCR) reports for 13 administrative regions. The number of gallbladder cancer cases with percentage, the crude incidence rate (CIR) and the age-standardised incidence rate (ASIR), stratified by regions, gender, and the years of diagnoses were analysed.

Results

A total of 1678 gallbladder cancer cases, 702 in males and 976 in females, were registered between 2004 and 2015. Saudi women and men in the 75 and above age-group were found to have the highest diagnosis rate of gallbladder cancer. In males, the overall ASIR among Saudi males was 1.1 per 100,000 (95% CI, 0.9 to 1.2). The Eastern region had the highest overall ASIR at 1.5 per 100,000 males, followed by Tabuk and Riyadh at 1.4 and 1.3 higher than other regions (F(12,143)=1.930, P<0.001). The overall ASIR among Saudi females was 1.6 per 100,000 (95% CI, 1.4 to 1.7). Riyadh had the highest overall ASIR at 2.4 per 100,000 females, followed by the Eastern region, and Qassim at 1.9 and 1.5, respectively, all higher than other provinces of the country (F(12,143)=2.496, P<0.005). The ASIR and CIR were lower among males than females (ratio 0.7).

Conclusion

Gallbladder cancer incidence is relatively low in Saudi Arabia. The rates were higher in females than males. ASIR showed variations between different provinces of Saudi Arabia. In females, the highest ASIR was in Riyadh. In males, ASIR was highest in the Eastern region of Saudi Arabia.

Molecular and Immunological Characterization of Biliary Tract Cancers: A Paradigm Shift Towards a Personalized Medicine

Biliary tract cancers (BTCs) are a group of rare cancers that account for up to 3–5% of cancer patients worldwide. BTCs include cholangiocarcinoma (CCA), gallbladder cancer (GBC), and ampulla of Vater cancer (AVC). They are frequently diagnosed at an advanced stage when the disease is often found disseminated. A late diagnosis highly compromises surgery, the only potentially curative option. Current treatment regimens include a combination of chemotherapeutic drugs gemcitabine with cisplatin that have a limited efficiency since more than 50% of patients relapse in the first year. More recently, an inhibitor of fibroblast growth factor receptor 2 (FGFR2) was approved as a second-line treatment, based on the promising results from the NCT02924376 clinical trial. However, novel secondary treatment options are urgently needed. Recent molecular characterization of CCA and GBC highlighted the molecular heterogeneity, etiology, and epidemiology in BTC development and lead to the classification of the extrahepatic CCA into four types: metabolic, proliferating, mesenchymal, and immune type. Differences in the immune infiltration and tumor microenvironment (TME) have been described as well, showing that only a small subset of BTCs could be classified as an immune “hot” and targeted with the immunotherapeutic drugs. This recent evidence has opened a way to new clinical trials for BTCs, and new drug approvals are highly expected by the medical community.

Effect of diabetes mellitus on survival in patients with gallbladder Cancer: a systematic review and meta-analysis

Background

Increasing evidences indicated that diabetes might increase the incidence of gallbladder cancer. However, no sufficient data has ever clarified the impact of diabetes on the survival of patients with gallbladder cancer.

Methods

We comprehensively searched PubMed, Embase, and the Cochrane Library databases through July 2019 in order to find sufficient eligible researches. The pooled hazard risks (HRs) and relative risks (RRs) with 95% confidence intervals (CIs) were calculated with either fix-effects or random-effects model. Due to the low gallbladder cancer mortality in general population, the RRs and standard mortality ratios (SMRs) were considered the similar estimates of the HRs.

Results

Ten eligible studies were included in this meta-analysis. Analysis of eight cohorts found that diabetes was closely associated with the mortality of gallbladder cancer (HR = 1.10; 95% CI: 1.06–1.14; P < 0.00001). However, the mortality in male diabetes patients was not higher than female patients (RR = 1.08, 95%CI = 0.57–2.04, P = 0.80).

Conclusions

These findings indicated that diabetes patients had a higher mortality of gallbladder cancer compared with non-diabetes.

Epidemiology of gallbladder cancer

According to GLOBOCAN 2018 data, gallbladder cancer (GBC) accounts for 1.2% of all global cancer diagnoses, but 1.7% of all cancer deaths. Only 1 in 5 GBC cases in the United States is diagnosed at an early stage, and median survival for advanced stage cancer is no more than about a year. The incidence of the disease is increasing in the developed world. Gallstones, biliary cysts, carcinogen exposure, typhoid, and Helicobacter pylori infection, and abnormal pancreaticobiliary duct junctions are all risk factors, many of which account for its geographical, ethnic and sex distribution. Genetics also plays a strong role, as about a quarter of GBC cases are considered familial, and certain ethnicities, such as Native Americans, are at far higher risk for the neoplasm. Prevention includes weight loss, vaccination against and treatment of bacterial infections, early detection and elimination of polyps and cysts, and avoidance of oral estrogen replacement therapy.

Epidemiological dimensions of the association between type 2 diabetes and cancer: A review of observational studies

Type 2 diabetes (T2D) is a major cause of complications and death in many countries. The possible causal relation between T2D and cancer has been the aim of many research investigations. In view of the importance of the topic we carried out a narrative review of observational studies to summarize the available evidence of the association between T2D and cancer. To deal with the problem of abundance of published studies, we reviewed up to December 2017, the literature of meta-analyses of observational studies first, then we reviewed cohort studies not reported in meta-analyses because of more recent publication. We found that the association of T2D with risk of colorectal cancer was robust, whereas the evidence of the associations with other cancer sites was lower. Some of the observed associations could be overestimated, due to publication bias, unmeasured confounders (such as obesity) and surveillance bias. In conclusion a probable causal association of T2D with risk of colorectal cancer was confirmed. A possible causal association with pancreatic, endometrial, hepatocellular and gallbladder carcinoma was also found. Substantial uncertainty exists for other cancer sites.

Type 1 diabetes mellitus and risk of cancer: a meta-analysis of observational studies

Objective

Previous observational studies have focused on the link between type 2 diabetes and the risk of cancer. However, the association between type 1 diabetes and the risk of cancer has not been well addressed. This study aimed to investigate the association between type 1 diabetes and the risk of cancer by using a meta-analysis of observational studies.

Methods

We searched PubMed and EMBASE for observational studies that examined the association between type 1 diabetes and cancer in April 2017. We calculated the pooled odds ratios (ORs) or relative risks (RRs) with confidence intervals (CIs) from individual studies based on a random-effects model meta-analysis.

Results

We included a total of 15 observational studies with two case-control studies and 13 cohort studies involving 31 893 cancer patients among a total of 1 915 179 participants in the final analysis. In the random-effects meta-analysis of all studies, patients with type 1 diabetes had an increased risk of cancer (OR or RR, 1.29; 95% CI, 1.09-1.52; n = 15; I2 = 95.2%). In the subgroup meta-analysis by type of cancer, type 1 diabetes significantly increased the risk of cancers of stomach, lung, pancreas, liver, ovary and kidney, whereas it significantly decreased the risk of breast cancer (OR or RR, 0.91; 95% CI, 0.86-0.95; n = 9; I2 = 0%).

Conclusion

This meta-analysis suggests that type 1 diabetes is associated with the increased risk of several types of cancer and the decreased risk of breast cancer. However, the plausible mechanisms for the decreased risk of breast cancer remain unclear. Further prospective studies with proper adjustment for possible confounding factors are warranted.

Diabetes mellitus and the risk of gastrointestinal cancer in women compared with men: a meta-analysis of cohort studies

Background

The increasing epidemic proportions of diabetes mellitus (DM) are a major cause of premature illness and death. However, whether DM confers the same excess risk of gastrointestinal cancer for women as it does for men remains controversial. The purpose of this study was to estimate the relation between DM and gastrointestinal cancer in women compared with men after accounting for other major risk factors based on cohort studies.

Methods

We performed a meta-analysis of cohort studies published through May 2017 from PubMed, Embase, and the Cochrane Library. Studies with cohort designs were stratified by sex and reported the relation between DM and esophageal cancer (EC), gastric cancer (GC), colorectal cancer (CRC), colon cancer (CC), rectal cancer (RC), hepatocellular carcinoma (HCC), or pancreatic cancer (PC) risk. The ratio of relative risk (RRR) between men and women was employed to measure the sex differences in the relation between DM and gastrointestinal cancer with a random effects model with inverse variance weighting.

Results

We included 38 cohort studies reporting data on 18,060,698 individuals. The pooled RRR indicated DM women was associated with an increased risk of GC (RRR: 1.14; 95%CI: 1.06–1.22; p < 0.001), while the risk of HCC was lower (RRR: 0.88; 95%CI: 0.79–0.99; p = 0.031) as compared with DM men. Further, there was no evidence of sex differences in the RRR between participants who had DM compared with those without DM for EC (p = 0.068), CRC (p = 0.618), and PC (p = 0.976). In addition, the pooled RRR showed a statistically significant association between DM and the risk of CC in women compared with men (RRR: 0.93; 95%CI: 0.86–1.00; p = 0.050), and there was no evidence of sex differences for RC among participants with DM compared to those without DM (p = 0.648). Finally, the sex differences of the comparison between DM and non-DM for gastrointestinal cancer risk at different sites were variable after stratification for different effect estimates.

Conclusions

The findings of this study suggested female-to-male RRR of DM was increased for GC, while reduced for HCC and CC. However, there were no sex differences for the relation between DM and the risk of EC, CRC, PC, and RC.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4351-4) contains supplementary material, which is available to authorized users.

Increased mortality for colorectal cancer patients with preexisting diabetes mellitus: an updated meta-analysis

Background

Although the preexisting diabetes mellitus (DM) is known to have a high risk for death in many cancers, its impact on the mortality for the colorectal cancer (CRC) patients is still uncertain. In this study, we conducted a meta-analysis to explore an association of DM with the survival for the CRC patients.

Materials and Methods

We made a relative data search from the public available databases including Medline and Embase with a cutoff date to Jan 31, 2017. Pooled hazard ratios (HRs) were calculated using either a fixed or random effect model. Trim and fill analysis was conducted to test and adjust for publication bias. Subgroup analyses were also performed for overall survival and all-cause mortality when stratified by tumor stage, geographical region, duration of follow-up, gender and subsite of cancer.

Results

Twenty-one eligible cohorts including 1,025,034 patients were identified and included in this meta-analysis review. The sample size for each analysis was ranged from 207 to 771,297 patients. It is revealed that with the preexisting DM, the CRC patients had a significantly increased all-cause mortality (pooled adjusted HR: 1.23; 95% CI: 1.11, 1.37) and decreased overall survival (pooled adjusted HR: 1.25, 95% CI: 1.19–1.31). But no difference was found for adjusted cancer-specific survival for the CRC patients with the preexisting DM compared with subjects without DM. These associations almost remained consistent after trim and fill adjustment and across those outcomes when stratified by site of cancer, tumor stage, population geography, study design, duration of follow-up, data resource or gender.

Conclusions

This meta-analysis review indicates that preexisting diabetes mellitus in CRC patients is severely associated with the worse overall survival but not with cancer-specific survival.

Sweetened Beverage Consumption and Risk of Biliary Tract and Gallbladder Cancer in a Prospective Study

BACKGROUND

Sugar-sweetened beverage consumption raises blood glucose concentration and has been positively associated with weight gain and type 2 diabetes, all of which have been implicated in the development of biliary tract cancer (BTC). This study examined the hypothesis that sweetened beverage consumption is positively associated with risk of BTC in a prospective study.

METHODS

The study population comprised 70 832 Swedish adults (55.9% men, age 45-83 years) from the Swedish Mammography Cohort and Cohort of Swedish Men who were free of cancer and diabetes and completed a food frequency questionnaire at baseline. Incident BTC case patients were ascertained through linkage with the Swedish Cancer Register. Cox proportional hazards regression model was used to analyze the data. All statistical tests were two-sided.

RESULTS

During a mean follow-up of 13.4 years, 127 extrahepatic BTC case patients (including 71 gallbladder cancers) and 21 intrahepatic BTC case patients were ascertained. After adjustment for other risk factors, women and men in the highest category of combined sugar-sweetened and artificially sweetened beverage consumption had a statistically significantly increased risk of extrahepatic BTC and gallbladder cancer. The multivariable hazard ratios for two or more servings per day (200 mL/serving) of sweetened beverages compared with no consumption were 1.79 (95% confidence interval [CI] = 1.02 to 3.13) for extrahepatic BTC and 2.24 (95% CI = 1.02 to 4.89) for gallbladder cancer. The corresponding hazard ratio for intrahepatic BTC was 1.69 (95% CI = 0.41 to 7.03).

CONCLUSIONS

These findings support the hypothesis that high consumption of sweetened beverages may increase the risk of BTC, particularly gallbladder cancer.

Prospective Study of Glycemic Load, Glycemic Index, and Carbohydrate Intake in Relation to Risk of Biliary Tract Cancer

OBJECTIVES

Diets that induce a high glycemic response might increase the risk of biliary tract cancer (BTC). We evaluated the hypothesis that diets with high glycemic load (GL) and high glycemic index (GI), which are measures of the glycemic effect of foods, are associated with an increased incidence of BTC.

METHODS

We used data from a population-based prospective study of 76,014 Swedish adults (age 45-83 years; 57% men) who were free of cancer and had completed a food-frequency questionnaire in the autumn of 1997. Incident cancer cases were ascertained by linkage with the Swedish Cancer Registry. Data were analyzed using Cox proportional hazards regression models.

RESULTS

During a mean follow-up of 13.3 years (1,010,777 person-years), we identified 140 extrahepatic BTC cases (including 77 gallbladder cancers) and 23 intrahepatic BTC cases. A high dietary GL was associated with an increased risk of BTC. The multivariable relative risks for the highest versus lowest quartile of dietary GL were 1.63 (95% confidence interval (95% CI), 1.01-2.63) for extrahepatic BTC, 2.14 (95% CI, 1.06-4.33) for gallbladder cancer, and 3.46 (95% CI, 1.22-9.84) for intrahepatic BTC. Dietary GI was statistically significantly positively associated with risk of extrahepatic BTC and gallbladder cancer. We observed no statistically significant association between carbohydrate intake and BTC risk, although all associations were positive.

CONCLUSION

Although these data do not prove a causal relationship, they are consistent with the hypothesis that high-GL and high-GI diets are associated with an increased risk of BTC.