Body mass index and risk of primary liver cancer: a meta-analysis of prospective studies

G-quadruplex forming regions in GCK and TM6SF2 are targets for differential DNA methylation in metabolic disease and hepatocellular carcinoma patients

The alarming increase in global rates of metabolic diseases (MetDs) and their association with cancer risk renders them a considerable burden on our society. The interplay of environmental and genetic factors in causing MetDs may be reflected in DNA methylation patterns, particularly at non-canonical (non-B) DNA structures, such as G-quadruplexes (G4s) or R-loops. To gain insight into the mechanisms of MetD progression, we focused on DNA methylation and functional analyses on intragenic regions of two MetD risk genes, the glucokinase (GCK) exon 7 and the transmembrane 6 superfamily 2 (TM6SF2) intron 2-exon 3 boundary, which harbor non-B DNA motifs for G4s and R-loops.Pyrosequencing of 148 blood samples from a nested cohort study revealed significant differential methylation in GCK and TM6SF2 in MetD patients versus healthy controls. Furthermore, these regions harbor hypervariable and differentially methylated CpGs also in hepatocellular carcinoma versus normal tissue samples from The Cancer Genome Atlas (TCGA). Permanganate/S1 nuclease footprinting with direct adapter ligation (PDAL-Seq), native polyacrylamide DNA gel electrophoresis and circular dichroism (CD) spectroscopy revealed the formation of G4 structures in these regions and demonstrated that their topology and stability is affected by DNA methylation. Detailed analyses including histone marks, chromatin conformation capture data, and luciferase reporter assays, highlighted the cell-type specific regulatory function of the target regions. Based on our analyses, we hypothesize that changes in DNA methylation lead to topological changes, especially in GCK exon 7, and cause the activation of alternative regulatory elements or potentially play a role in alternative splicing.Our analyses provide a new view on the mechanisms underlying the progression of MetDs and their link to hepatocellular carcinomas, unveiling non-B DNA structures as important key players already in early disease stages.

Advances in biomedical applications of vitamin D for VDR targeted management of obesity and cancer

BACKGROUND

1,25(OH)2D3 is a fat-soluble vitamin, involved in regulating Ca2+ homeostasis in the body. Its storage in adipose tissue depends on the fat content of the body. Obesity is the result of abnormal lipid deposition due to the prolonged positive energy balance and increases the risk of several cancer types. Furthermore, it has been associated with vitamin D deficiency and defined as a low 25(OH)2D3 blood level. In addition, 1,25(OH)2D3 plays vital roles in Ca2+-Pi and glucose metabolism in the adipocytes of obese individuals and regulates the expressions of adipogenesis-associated genes in mature adipocytes.

SCOPE AND APPROACH

The present contribution focused on the VDR mediated mechanisms interconnecting the obese condition and cancer proliferation due to 1,25(OH)2D3-deficiency in humans. This contribution also summarizes the identification and development of molecular targets for VDR-targeted drug discovery.

KEY FINDINGS AND CONCLUSIONS

Several studies have revealed that cancer development in a background of 1,25(OH)2D3 deficient obesity involves the VDR gene. Moreover, 1,25(OH)2D3 is also known to influence several cellular processes, including differentiation, proliferation, and adhesion. The multifaceted physiology of obesity has improved our understanding of the cancer therapeutic targets. However, currently available anti-cancer drugs are notorious for their side effects, which have raised safety issues. Thus, there is interest in developing 1,25(OH)2D3-based therapies without any side effects.

A Retrospective Cohort Study From the National Inpatient Sample Database (2016-2019): Does Obesity Affect the Outcomes of Hospitalization Due to Hepatocellular Carcinoma?

INTRODUCTION

Obesity is commonly reported to be associated with hepatocellular carcinoma (HCC) along with higher risks of mortality. However, there is a significant research gap regarding the outcomes of hospitalization due to HCC among obese patients compared to those without obesity. This study compares the outcomes of hospitalization among those two groups.

METHODS

 A total of 50,845 patients admitted from 2016 to 2019 with a principal admission diagnosis of HCC were identified using the International Classification of Disease 10 (ICD-10) coding from the National Inpatient Sample (NIS) database. Patients with a body mass index (BMI) >30 were stratified into the obese cohort, and those with BMI ≤30 into the non-obese cohort as per the ICD-10 coding criteria for obesity based on BMI. The primary outcome of the study was mortality, whereas the length of stay, total hospitalization charges, acute kidney injury (AKI), sepsis, and shock were the secondary outcomes. We also compared additional complications such as ascites, portal hypertension, acute liver failure, disseminated intravascular coagulation (DIC), hepatic encephalopathy, and hepatorenal syndrome between the two groups. A multivariate regression model was used to estimate the effect of obesity on outcomes of hospitalization due to HCC.

RESULTS

The obese cohort comprised 10.64% of the study population, whereas the non-obese cohort comprised 89.36% of the study population. Compared to the non-obese cohort, the obese cohort of patients with HCC were more likely to have a higher comorbidity index (CCI ≥4: 79.76% in the obese vs 71.17 % in the non-obese cohort). Obesity was found to be a protective factor for in-hospital mortality; that is, the odds of in-hospital mortality among the obese cohort was 0.713 times than that of the non-obese group of patients with HCC. The obese cohort had a higher mean length of stay (6.3 days vs 5.6 days; p value: <0.001) and total hospitalization charges (109,108$ vs 85,406$; p value: <0.001), which was further validated on multivariate analysis. The obese cohort had 1.26 times odds of developing AKI compared to the non-obese cohort (p value: 0.005). Sepsis, shock, and other complications such as acute liver failure, DIC, hepatic encephalopathy, hepatorenal syndrome, and portal hypertension were not significantly different between the two groups.

CONCLUSION

 Obesity was associated with reduced in-hospital mortality among patients with HCC. However, obese patients with HCC were found to have higher healthcare resource utilization in terms of length of stay and total hospitalization charge along with the development of AKI. Clinicians should be mindful of the potential longer length of stay and associated complications such as AKI while managing obese patients with HCC. Contrary to commonly held notions, obesity and its relation with in-hospital mortality reported in this study warrants further explorative research.

Insulin Resistance: The Increased Risk of Cancers

Insulin resistance, also known as impaired insulin sensitivity, is the result of a decreased reaction of insulin signaling to blood glucose levels. This state is observed when muscle cells, adipose tissue, and liver cells, improperly respond to a particular concentration of insulin. Insulin resistance and related increased plasma insulin levels (hyperinsulinemia) may cause metabolic impairments, which are pathological states observed in obesity and type 2 diabetes mellitus. Observations of cancer patients confirm that hyperinsulinemia is a major factor influencing obesity, type 2 diabetes, and cancer. Obesity and diabetes have been reported as risks of the initiation, progression, and metastasis of several cancers. However, both of the aforementioned pathologies may independently and additionally increase the cancer risk. The state of metabolic disorders observed in cancer patients is associated with poor outcomes of cancer treatment. For example, patients suffering from metabolic disorders have higher cancer recurrence rates and their overall survival is reduced. In these associations between insulin resistance and cancer risk, an overview of the various pathogenic mechanisms that play a role in the development of cancer is discussed.

Trends in the burden of most common obesity-related cancers in 16 Southern Africa development community countries, 1990-2019. Findings from the global burden of disease study

Background

Obesity-related cancers in the 16 Southern African Development Community (SADC) countries is quite prominent. The changes and time trends of the burden of obesity-related cancers in developing countries like SADC remain largely unknown. A descriptive epidemiological analysis was conducted to assess the burden of obesity-related cancers, (liver, esophageal, breast, prostate, colon/rectal, leukemia, ovarian, uterine, pancreatic, kidney, gallbladder/biliary tract, and thyroid cancers) in SADC countries.

Methods

Data from the 2019 Global Burden of Diseases Study was used. Deaths extracted from vital registration, verbal autopsies and ICD codes. Cancer-type, mortality and prevalence per 100,000 population and 95% uncertainty intervals (UIs) were calculated using the Cause of Death Ensemble model and Spatio-Temporal Gaussian process with mixed effects regression models. Annual rates of change (AROCs) between 1990 and 2019 and the corresponding UIs were calculated.

Results

The top age-standardized mortality rates per 100,000 in 2019 for males were leukemia, 20.1(14.4-26.4), esophageal cancer, 15.1 (11.2-19.1), and colon and rectal cancer, 10.3 (8.6-12.6). For females, breast cancer, 20.6 (16.6-25.0), leukemia, 17.1 (11.4-23.7), and esophageal cancer, 8.3 (5.5-10.7), had the leading mortality rates. For males, AROC substantial (p < 0.05) increase for kidney cancer for 11 of the countries (AROC from 0.41% to 1.24%), colon cancer for eight of the countries (from 0.39% to 0.92%), and pancreatic cancer for seven countries (from 0.26% to 1.01%). In females, AROC showed substantial increase for pancreatic cancer for 13 of the countries from (0.34%-1.67%), nine countries for kidney cancer (from 0.27% to 1.02%), seven countries each for breast cancer (0.35%-1.13%), and ovarian cancer (from 0.33% to 1.21%).

Conclusions

There is need for location-specific and culturally appropriate strategies for better nutrition and weight control, and improved screening for all cancers. Health promotion messaging should target kidney, colon, pancreatic, and breast cancers and encourage clinically tested methods of reducing BMI such as increasing personal physical activity and adoption of effective dietary regimes.

MASLD and the Development of HCC: Pathogenesis and Therapeutic Challenges

Metabolic-dysfunction-associated steatotic liver disease (MASLD, previously known as non-alcoholic fatty liver disease (NAFLD)) represents a rapidly increasing cause of chronic liver disease and hepatocellular carcinoma (HCC), mirroring increasing rates of obesity and metabolic syndrome in the Western world. MASLD-HCC can develop at an earlier stage of fibrosis compared to other causes of chronic liver disease, presenting challenges in how to risk-stratify patients to set up effective screening programmes. Therapeutic decision making for MASLD-HCC is also complicated by medical comorbidities and disease presentation at a later stage. The response to treatment, particularly immune checkpoint inhibitors, may vary by the aetiology of the disease, and, in the future, patient stratification will be key to optimizing the therapeutic pathways.

NASH/NAFLD-Related Hepatocellular Carcinoma: An Added Burden

Hepatocellular carcinoma (HCC) is the most frequently found primary malignancy of the liver, showing an accelerated upward trend over the past few years and exhibiting an increasing relationship with metabolic syndrome, obesity, dyslipidemia and type 2 diabetes mellitus. The connection between these risk factors and the occurrence of HCC is represented by the occurrence of non-alcoholic fatty liver disease (NAFLD) which later, based on genetic predisposition and various triggers (including the presence of chronic inflammation and changes in the intestinal microbiome), may evolve into HCC. HCC in many cases is diagnosed at an advanced stage and can be an incidental finding. We present such a scenario in the case of a 41-year-old male patient who had mild obesity and mixed dyslipidemia, no family or personal records of digestive pathologies and who recently developed a history of progressive fatigue, dyspepsia and mild upper abdominal discomfort initially thought to be linked to post-COVID syndrome, as the patient had COVID-19 pneumonia a month prior. The abdominal ultrasound revealed a mild hepatomegaly with bright liver aspect of the right lobe (diffuse steatosis), a large zone of focal steatosis (segments IV, III and II) and a left lobe tumoral mass, highly suggestive of malignancy. Point shear wave elastography at the right lobe ruled out an end-stage chronic liver disease. Additional laboratory investigations, imaging studies (magnetic resonance imaging) and histopathological examination of liver fragments confirmed a highly aggressive HCC, with poorly differentiation-G3, (T4, N 1M 0) and stage IVA, associated with nonalcoholic steatohepatitis (NASH). A sorafenib course of treatment was attempted, but the patient discontinued it due to severe side effects. The subsequent evolution was extremely unfavorable, with rapid degradation, a few episodes of upper digestive bleeding, hepatic insufficiency and mortality in a couple of months. Conclusions: Diagnosis of NASH-related HCC is either an accidental finding or is diagnosed at an advanced stage. In order to earn time for a proper treatment, it becomes important to diagnose it at an early stage, for which regular check-ups should be performed in groups having the risk factors related to it. Patients suffering from obesity and mixed dyslipidemia should undergo periodic abdominal ultrasound examinations. This should be emphasized even more in the cases showing NASH. Complaints of any kind post-COVID-19 should be dealt with keenly as little is yet known about its virulence and its long-term side effects.

A Review of Incidence and Related Risk Factors in the Development of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is a primary liver malignancy, ranking as the seventh most common cancer globally and the second leading cause of deaths due to cancer. This review examines the incidence of HCC, its associated risk factors, and constantly changing global trends. Incidence has been noted to be varying worldwide, particularly due to environmental and infectious risk factors. Chronic hepatitis B (HBV) and C (HCV) virus infections, alcohol abuse, aflatoxin exposure, diabetes, obesity, and tobacco consumption are some of the leading risk factors noted. Eastern Asia and sub-Saharan Africa were noted to have the highest disease burden for HCC, with China representing a considerably large majority. On the contrary, the United States reports a lower HCC incidence overall due to improved vaccination programs against HBV; however, with a rising incidence of prominent risk factor in non-alcoholic fatty liver disease (NAFLD), the trend may very well change. Gender disparities were noted to be evident with men experiencing higher rates of HCC compared to women, which may be due to various environmental and biological factors, including alcohol intake, smoking, and androgen hormone levels. Currently, efforts to reduce the overall incidence of HCC include universal HBV vaccinations, antiviral therapies, aflatoxin prevention measures, genetic screening for hereditary hemochromatosis, and early ultrasound evaluation in patients with liver cirrhosis. Understanding these evolving trends and risk factors is essential in combating the rising HCC incidence, especially in Western countries, where risk factors, such as obesity, diabetes, and metabolic disorders, are on the rise.

Meeting at the Crossroad between Obesity and Hepatic Carcinogenesis: Unique Pathophysiological Pathways Raise Expectations for Innovative Therapeutic Approaches

The escalating global prevalence of obesity and its intricate association with the development of hepatocellular carcinoma (HCC) pose a substantial challenge to public health. Obesity, acknowledged as a pervasive epidemic, is linked to an array of chronic diseases, including HCC, catalyzing the need for a comprehensive understanding of its molecular underpinnings. Notably, HCC has emerged as a leading malignancy with rising incidence and mortality. The transition from viral etiologies to the prominence of metabolic dysfunction-associated fatty liver disease (MAFLD)-related HCC underscores the urgent need to explore the intricate molecular pathways linking obesity and hepatic carcinogenesis. This review delves into the interwoven landscape of molecular carcinogenesis in the context of obesity-driven HCC while also navigating using the current therapeutic strategies and future prospects for combating obesity-related HCC. We underscore the pivotal role of obesity as a risk factor and propose an integrated approach encompassing lifestyle interventions, pharmacotherapy, and the exploration of emerging targeted therapies. As the obesity-HCC nexus continues to challenge healthcare systems globally, a comprehensive understanding of the intricate molecular mechanisms and innovative therapeutic strategies is imperative to alleviate the rising burden of this dual menace.

Metabolic profile predicts incident cancer: A large-scale population study in the UK Biobank

BACKGROUND AND AIMS

Analyses to predict the risk of cancer typically focus on single biomarkers, which do not capture their complex interrelations. We hypothesized that the use of metabolic profiles may provide new insights into cancer prediction.

METHODS

We used information from 290,888 UK Biobank participants aged 37 to 73 years at baseline. Metabolic subgroups were defined based on clustering of biochemical data using an artificial neural network approach and examined for their association with incident cancers identified through linkage to cancer registry. In addition, we evaluated associations between 38 individual biomarkers and cancer risk.

RESULTS

In total, 21,973 individuals developed cancer during the follow-up (median 3.87 years, interquartile range [IQR] = 2.03-5.58). Compared to the metabolically favorable subgroup (IV), subgroup III (defined as "high BMI, C-reactive protein & cystatin C") was associated with a higher risk of obesity-related cancers (hazard ratio [HR] = 1.26, 95 % CI = 1.21 to 1.32) and hematologic-malignancies (e.g., lymphoid leukemia: HR = 1.83, 95%CI = 1.44 to 2.33). Subgroup II ("high triglycerides & liver enzymes") was strongly associated with liver cancer risk (HR = 5.70, 95%CI = 3.57 to 9.11). Analysis of individual biomarkers showed a positive association between testosterone and greater risks of hormone-sensitive cancers (HR per SD higher = 1.32, 95%CI = 1.23 to 1.44), and liver cancer (HR = 2.49, 95%CI =1.47 to 4.24). Many liver tests were individually associated with a greater risk of liver cancer with the strongest association observed for gamma-glutamyl transferase (HR = 2.40, 95%CI = 2.19 to 2.65).

CONCLUSIONS

Metabolic profile in middle-to-older age can predict cancer incidence, in particular risk of obesity-related cancer, hematologic malignancies, and liver cancer. Elevated values from liver tests are strong predictors for later risk of liver cancer.

KETOgenic diet therapy in patients with HEPatocellular adenoma: study protocol of a matched interventional cohort study

INTRODUCTION

Hepatocellular adenoma (HCA) is an uncommon, solid and benign liver lesion, mainly occurring in women using oral contraceptives. Patients are advised to stop using oral contraceptives (OC) and, as overweight is frequently observed, dietary restrictions. Metabolic changes are assumed to play a role and it has been suggested that diet may help to reduce tumour size. A low-calorie ketogenic diet (LCKD) has been shown to induce weight loss and multiple metabolic changes, including the reduction of portal insulin concentrations, which downregulates hepatic growth hormone receptors. Weight reduction and an LCKD can potentially reduce the size of HCAs.

METHODS AND ANALYSIS

We designed a matched, interventional cohort study to determine the effect of an LCKD on the regression of HCA. The study population consists of female subjects with an HCA, 18-50 years of age, body mass index>25 kg/m², who are entering a surveillance period including cessation of OC. A historical control group will be matched. The intervention consists of an LCKD (approximately 35 g carbohydrate/1500 kcal/day) for 3 months, followed by a less strict LCKD for 3 months (approximately 60 g carbohydrate/1500 kcal/day). Main study endpoint is the diameter of the HCA after 6 months, as compared with the historic control group. Secondary endpoints include adherence, quality of life, change in physical activity, liver fat content, body weight, body composition and resting energy expenditure.

ETHICS AND DISSEMINATION

The medical ethical committee has approved the study protocol, patient information files and consent procedure and other study-related documents and procedures.

TRIAL REGISTRATION NUMBER

NL75014.078.20; Pre-results. https://www.trialregister.nl/trial/9092.

Unique situation of hepatocellular carcinoma in Egypt: A review of epidemiology and control measures

Hepatocellular carcinoma (HCC) is the sixth most common primary malignancy worldwide, and the third most common cause of death among cancers worldwide. HCC occurs in several pre-existing conditions, including hepatitis C, hepatitis B virus, and non-alcoholic cirrhosis. Egypt used to be the country with the heaviest hepatitis C virus (HCV) burden. The relationship between HCV and HCC is an important research area. In Egypt, HCC is a significant public health problem. A possible cause for the increasing rates of detection of HCC in Egypt is the mass screening program that was carried by the government for detecting and treating HCV. A multidisciplinary approach is now widely applied to HCC management in health centers all over Egypt. Different treatment modalities are available in Egypt, with success rates comparable to global rates. The Egyptian health authorities have made the elimination of HCV from Egypt a special priority, and this approach should lead to a decrease in number of HCC cases in the near future. In this article we review the current situation of HCC in Egypt, including epidemiological aspects, relevant risk factors for HCC development, strategies, and efforts established by health authorities for the screening and prevention of both HCV and HCC in Egypt. We highlight the different modalities for HCC treatment.

Non-alcoholic steatohepatitis and risk of hepatocellular carcinoma

ABSTRACT

The emergence of non-alcoholic fatty liver disease (NAFLD) as the leading chronic liver disease worldwide raises some concerns. In particular, NAFLD is closely tied to sedentary lifestyle habits and associated with other metabolic diseases, such as obesity and diabetes. At the end of the disease spectrum, non-alcoholic steatohepatitis (NASH) may progress to cirrhosis and hepatocellular carcinoma (HCC), representing a serious health problem to modern society. Recently, an increasing number of HCC cases originating from this progressive disease spectrum have been identified, with different levels of severity and complications. Updating the current guidelines by placing a bigger focus on this emerging cause and highlighting some of its unique features is necessary. Since, the drivers of the disease are complex and multifactorial, in order to improve future outcomes, having a better understanding of NASH progression into HCC may be helpful. The risks that can promote disease progression and currently available management strategies employed to monitor and treat NASH-related HCC make up the bulk of this review.

Low serum magnesium concentration is associated with the presence of viable hepatocellular carcinoma tissue in cirrhotic patients

This study aimed to ascertain, for the first time, whether serum magnesium (Mg) concentration is affected by the presence of hepatocellular carcinoma (HCC). We retrospectively enrolled consecutive cirrhotic patients with a diagnosis of HCC (n = 130) or without subsequent evidence of HCC during surveillance (n = 161). Serum levels of Mg were significantly (P < 0.001) lower in patients with HCC than in those without (median [interquartile range]: 1.80 [1.62–1.90] mg/dl vs. 1.90 [1.72–2.08] mg/dl). On multivariate logistic regression, low serum Mg was associated with the presence of HCC (OR 0.047, 95% CI 0.015–0.164; P < 0.0001), independently from factors that can influence magnesaemia and HCC development. In a subset of 94 patients with HCC, a linear mixed effects model adjusted for confounders showed that serum Mg at diagnosis of HCC was lower than before diagnosis of the tumor (β = 0.117, 95% CI 0.039–0.194, P = 0.0035) and compared to after locoregional treatment of HCC (β = 0.079, 95% CI 0.010–0.149, P = 0.0259), with two thirds of patients experiencing these changes of serum Mg over time. We hypothesize that most HCCs, like other cancers, may be avid for Mg and behave like a Mg trap, disturbing the body’s Mg balance and resulting in lowering of serum Mg levels.

Healthcare Disparities Identified Between Hmong and Other Asian Origin Groups Living with Chronic Hepatitis B Infection in Sacramento County 2014-2017

Chronic hepatitis B (CHB) disproportionately affects non-US born Asians. The Hmong have been shown to have the highest rates of CHB and mortality from liver cancer compared to other Asian groups. From September 2014 to September 2017, testing for CHB within Sacramento County was conducted through community-based testing events and an electronic health record alert that identified Asian patients by surname. Demographic and laboratory data were collected for analysis and patients were followed through the study period to assess linkage to care and treatment to compare differences between Asian origin groups. Of 4350 patients tested for CHB, 318 (7.3%) were HBsAg positive, including 90 Chinese, 47 Hmong, and 101 Vietnamese. Hmong were more likely to have Medicaid insurance compared to other Asian origin groups (15%, p < 0.001). Hmong had significantly lower rates of hepatitis B DNA testing (p < 0.001), referral to hepatology (p < 0.001), attendance of first (p < 0.001) and second medical visit (p = 0.0003), and lower rates of antiviral treatment compared to other Asian origin groups. Hmong also had the highest proportion of non-English speakers (p < 0.001). Hmong patients in the Sacramento CHB testing and linkage to care program experience socioeconomic disadvantages compared to Vietnamese and Chinese patients. These factors may contribute to decreased linkage of care and decreased anti-viral treatment rates for CHB.

Obesity and the risk of primary liver cancer: A systematic review and meta-analysis

Background/Aims

In this systematic review and meta-analysis, we aimed to clarify the effect of obesity on the occurrence of and mortality from primary liver cancer.

Methods

This study was conducted using a systematic literature search of MEDLINE, EMBASE, and the Cochrane Library until November 2018 using the primary keywords “obesity,” “overweight,” “body mass index (BMI),” “body weight,” “liver,” “cancer,” “hepatocellular carcinoma,” “liver cancer,” “risk,” and “mortality.” Studies assessing the relationship between BMI and occurrence of or mortality from primary liver cancer in prospective cohorts and those reporting hazard ratios (HRs) or data that allow HR estimation were included.

Results

A total of 28 prospective cohort studies with 8,135,906 subjects were included in the final analysis. These included 22 studies with 6,059,561 subjects for cancer occurrence and seven studies with 2,077,425 subjects for cancer-related mortality. In the meta-analysis, an increase in BMI was associated with the occurrence of primary liver cancer (HR, 1.69; 95% confidence interval, 1.50–1.90, I²=56%). A BMI-dependent increase in the risk of occurrence of primary liver cancer was reported. HRs were 1.36 (95% CI, 1.02–1.81), 1.77 (95% CI, 1.56–2.01), and 3.08 (95% CI, 1.21–7.86) for BMI >25 kg/m², >30 kg/m², and >35 kg/m², respectively. Furthermore, increased BMI resulted in enhanced liver cancer-related mortality (HR, 1.61; 95% CI, 1.14–2.27, I²=80%).

Conclusions

High BMI increases liver cancer mortality and occurrence of primary liver cancer. Obesity is an independent risk factor for the occurrence of and mortality from primary liver cancer.

Associations of general obesity and central obesity with the risk of hepatocellular carcinoma in a Korean population: A national population-based cohort study

Numerous previous studies have shown an association between general obesity and hepatocellular carcinoma (HCC). However, relatively few reports on the association of central obesity and HCC are available in Asian populations. Therefore, we investigated the association between WC representing central obesity and the risk of HCC in addition to BMI representing general obesity and the risk of HCC in Korea. A total of 10 505 818 participants who received the National Health Insurance Service (NHIS) health checkups in 2009 were screened for study eligibility, and 26 979 cases of HCC occurred during the 7.3 years of mean follow-up. General obesity increased the risk of HCC with hazard ratios (HRs) of 1.14 (95% CI, 1.11-1.18) for BMI 25.0-<30.0 kg/m² and 1.52 (95% CI, 1.43-1.61) for BMI ≥30 kg/m² compared to those whose BMI is within the normal range. Central obesity was also associated with a higher risk of HCC. For the participants with a WC ≥105 cm in men and WC ≥100 cm in women, the risk of HCC was higher than that of the reference group (HR = 1.69, 95% CI, 1.54-1.85). The HRs were 1.13 (95% CI, 1.07-1.19) for nonobese participants with central obesity, and 1.34 (95% CI, 1.30-1.38) for obese participants with central obesity compared to those without both conditions. Our findings suggest that the risk of HCC increases even more when general obesity is combined with central obesity. Moreover, central obesity is associated with the risk of HCC, regardless of general obesity.

Independent and Joint Associations between Serum Calcium, 25-Hydroxy Vitamin D, and the Risk of Primary Liver Cancer: A Prospective Nested Case-Control Study

BACKGROUND

Accumulating evidence has shown that serum calcium and vitamin D may be associated with or influence various cancer risks. However, no prospective studies have evaluated the independent and joint associations between prediagnostic levels of serum calcium and vitamin D and future risk of incident primary liver cancer.

METHODS

We used a nested case-control design to evaluate subjects over 22 years of follow-up. Serum calcium, 25-hydroxy vitamin D [25(OH)D], and three markers of hepatitis B virus and hepatitis C virus were measured in baseline serum from 226 incident primary liver cancer cases and 1,061 matched controls. We calculated ORs and 95% confidence intervals (CI) using logistic regression to estimate the associations between calcium, 25(OH)D, and primary liver cancer risk.

RESULTS

Multivariable adjusted models showed that subjects with both low (ORLow/Medium = 1.48, 95% CI = 1.01-2.17) or high (ORHigh/Medium = 1.92, 95% CI = 1.34-2.76) calcium had an increased primary liver cancer risk, while those with high 25(OH)D had a decreased risk of primary liver cancer (ORHigh/Medium = 0.54, 95% CI = 0.35-0.82). In joint analyses, when compared with subjects with medium calcium and 25(OH)D, subjects with high calcium and medium 25(OH)D had elevated odds of developing primary liver cancer (OR = 1.89, 95% CI = 1.17-3.05); those with medium calcium and high 25(OH)D had reduced odds of developing primary liver cancer (OR = 0.34, 95% CI = 0.17-0.67); and subjects in other classifications of calcium and serum 25(OH)D levels had no change in the odds of developing primary liver cancer (all P > 0.05).

CONCLUSIONS

In a nutrient-deficient population, we found that serum calcium and serum 25(OH)D could potentially be modifiable risk or protective factors.

IMPACT

Our findings provide potential targets for primary liver cancer prevention and control.

Obesity and liver cancer

Obesity prevalence is rapidly increasing worldwide. It is associated with huge economic and health costs due to its clinical consequences, which includes increased incidence of type 2 diabetes, cardiovascular diseases, and development of different malignancies. In particular, obesity is an independent risk factor for the development of hepatocellular carcinoma (HCC). Indeed, obesity is highly prevalent in patients with non-alcoholic fatty liver disease (NAFLD) that is becoming one of the most frequent causes of liver disease worldwide. NAFLD-related HCC is the most rapidly growing indication for liver transplantation in many countries. The higher mortality rates found in obese HCC patients might be related not only to a worse outcome after HCC treatments, but also to a delayed diagnosis related to a low frequency and a poorer quality of abdominal ultrasonography surveillance that is the test universally used for HCC screening. Given its diffusion, obesity is frequently present in patients with chronic liver diseases related to different etiologies, and in these cases it may increase the HCC risk, acting as an additional co-factor. Indeed, growing evidence demonstrates that a healthy diet and regular physical activity may have an impact in reducing the overall HCC risk. Finally, an impact of obesity in the development of intrahepatic cholangiocarcinoma has been postulated, but more extensive studies are needed to definitively confirm this association.

Overweight and Obesity as Independent Factors for Increased Risk of Hepatocellular Cancer-Related Mortality: A Meta-Analysis

Obesity is related to the amplified risk of developing hepatocellular cancer, but its outcome on hepatocellular cancer-related mortality remains uncertain. Hence, the present study aimed to perform a meta-analysis study to evaluate the relationship between weight and hepatocellular cancer-related deaths. Through a systematic literature search up to December 2019, 7 observational studies with 2,349,834 subjects, 4834 hepatocellular cancer-related deaths were identified reporting relationships between body mass index (BMI), and hepatocellular cancer-related mortality. Odd ratio (OR) with 95% confidence intervals (CIs) was calculated comparing obese, BML > 30kg/m², and overweight, BMI, 25-29.9 kg/m² to subjects with normal BMI using the dichotomous method with a random-effect model. In obese subjects, males (OR, 1.84; 95% CI, 1.25-2.70) and females (OR, 1.26; 95% CI, 1.11-1.44), had higher hepatocellular cancer-related mortality compared to normal BMI subjects. However, overweight males (OR, 1.12; 95% CI, 0.98-1.28) and overweight females (OR, 1.06; 95% CI, 0.95-1.18), did not have such risk with moderate heterogeneity. The extent of increased mortality was higher in obese males compared to obese females. The impact of obesity on hepatocellular cancer-related mortality was observed in all populations with less extant in the black population. Based on this meta-analysis, obesity may have an independent relationship with up to the 1.84-fold risk of hepatocellular cancer-related mortality. This relationship was more pronounced in males than in females. Key teaching pointsBeing overweight is related to the amplified risk of developing hepatocellular cancer.Obesity's affect on hepatocellular cancer-related mortality remains uncertain.Based on this meta-analysis, obesity may have an independent relationship with up to the 1.84-fold risk of hepatocellular cancer-related mortality.This relationship was more pronounced in males than in females.

Waist Circumference and Risk of Liver Cancer: A Systematic Review and Meta-Analysis of over 2 Million Cohort Study Participants

PURPOSE

Liver cancer is the sixth most common type of cancer worldwide, and waist circumference (WC) is associated with its risk beyond body mass index (BMI). This dose-response meta-analysis was performed to investigate the association between WC and the risk of incident liver cancer using prospective cohort studies.

METHODS

A comprehensive systematic search was conducted in MEDLINE/PubMed, Web of Science databases, Scopus, and Coch-rane from inception to May 2019. Studies with retrospective or prospective cohort design that reported hazard ratio (HR), risk ratio, or odds ratio, and the corresponding 95% confidence intervals (CI) for liver cancer based on WC categories were included in this meta-analysis. Combined HRs with 95% CIs was estimated by DerSimonian and Laird random-effects models.

RESULTS

Associations between WC and liver cancer were reported in 5 articles with 2,547,188 participants. All studies were published between 2013 and 2019. Pooled results showed a strong significant association with minimum heterogeneity between WC and risk of liver cancer (HR 1.59, 95% CI 1.38-1.83, p_{heterogeneity} = 0.42: I² = 0%). Moreover, a dose-response model indicated a significant positive association between WC and risk of liver cancer (exp(b) = 1.018, p < 0.001).

CONCLUSIONS

This systematic review and dose-response meta-analysis highlights WC as a significant risk factor related to the incidence of liver cancer.

HNF4α-Deficient Fatty Liver Provides a Permissive Environment for Sex-Independent Hepatocellular Carcinoma

The incidence of hepatocellular carcinoma (HCC) is on the rise worldwide. Although the incidence of HCC in males is considerably higher than in females, the projected rates of HCC incidence are increasing for both sexes. A recently appreciated risk factor for HCC is the growing problem of nonalcoholic fatty liver disease, which is usually associated with obesity and the metabolic syndrome. In this study, we showed that under conditions of fatty liver, female mice were more likely to develop HCC than expected from previous models. Using an inducible knockout model of the tumor-suppressive isoform of hepatocyte nuclear factor 4 alpha ("P1-HNF4α") in the liver in combination with prolonged high fat (HF) diet, we found that HCC developed equally in male and female mice as early as 38 weeks of age. Similar sex-independent HCC occurred in the "STAM" model of mice, in which severe hyperglycemia and HF feeding results in rapid hepatic lipid deposition, fibrosis, and ultimately HCC. In both sexes, reduced P1-HNF4α activity, which also occurs under chronic HF diet feeding, increased hepatic lipid deposition and produced a greatly augmented circadian rhythm in IL6, a factor previously linked with higher HCC incidence in males. Loss of HNF4α combined with HF feeding induced epithelial-mesenchymal transition in an IL6-dependent manner. Collectively, these data provide a mechanism-based working hypothesis that could explain the rising incidence of aggressive HCC. SIGNIFICANCE: This study provides a mechanism for the growing incidence of hepatocellular carcinoma in both men and women, which is linked to nonalcoholic fatty liver disease.

Excess Body Weight and the Risk of Liver Cancer: Systematic Review and a Meta-Analysis of Cohort Studies

Objective: To update and expand the previous meta-analysis including all prospective studies on the issue of the associations between overweight, obesity, and liver cancer risk. We also performed a meta-regression to investigate a potential nonlinear and/or linear association between body mass index (BMI) and liver cancer risk.Methods: Literature search was conducted in four libraries from the beginning of indexing for each database to 1st September, 2018.Results: The summary risk estimate was statistically significant on the association between overweight and the risk of liver cancer incidence (relative ratio [RR] = 1.19). The RRs were significantly stronger in people with known liver disease with overweight than in the general population with overweight (RR = 1.50 vs. RR = 1.10; P_difference = .02). The meta-analysis showed an increase by 87% on the risk of liver cancer incidence in obesity categories, relative to categories of normal BMI (RR = 1.87, P < .01). Moreover, the results showed that, overweight was associated with 9% increased and obesity with 66% increased for risk of liver cancer mortality. In linear model, the relative risks of liver cancer were 1.32 for continuous BMI per 5 kg/m² increase.Conclusion: This meta-analysis supports the hypothesis that overweight, obesity may significantly increase liver cancer risk.

Obesity is Independently Associated With Increased Risk of Hepatocellular Cancer-related Mortality: A Systematic Review and Meta-Analysis

OBJECTIVE

Excess body weight is associated with increased risk of developing hepatocellular cancer (HCC), but its effect on HCC-related mortality remains unclear. We performed a systematic review and meta-analysis to assess the association between premorbid obesity and HCC-related mortality.

MATERIALS AND METHODS

Through a systematic literature search-up to March 2016, we identified 9 observational studies (1,599,453 individuals, 5705 HCC-related deaths) reporting the association between premorbid body mass index (BMI), and HCC-related mortality. We estimated summary adjusted hazard ratio (aHR) with 95% confidence intervals (CIs), comparing obese (BMI>30 kg/m(2)) and overweight (BMI, 25 to 29.9 kg/m(2)) individuals with normal BMI individuals using random-effects model.

RESULTS

On meta-analysis, compared with individuals with normal BMI, obese (aHR, 1.95; 95% CI, 1.46-2.46), but not overweight individuals (aHR, 1.08; 95% CI, 0.97-1.21), had higher HCC-related mortality, with moderate heterogeneity. On subgroup analysis, magnitude of increased mortality was higher in obese men (aHR, 2.50; 95% CI, 2.02-3.09; 3 studies) as compared with obese women (aHR, 1.45; 95% CI, 1.08-1.97; 2 studies). The impact of premorbid obesity on HCC-related mortality was observed only in western populations (aHR, 2.10; 95% CI, 1.77-2.48; 4 studies), but not Asian populations (aHR, 1.10; 95% CI, 0.63-1.92; 1 study). There was limited assessment of competing risk because of advanced liver disease.

CONCLUSIONS

On the basis of this meta-analysis, premorbid obesity may be independently associated with a 2-fold risk of HCC-related mortality. This association was more pronounced in men and western populations. Strategies targeting obesity-associated metabolic abnormalities may provide novel pathways for HCC therapy.

Pooled Analysis of the Associations between Body Mass Index, Total Cholesterol, and Liver Cancer-related Mortality in Japan

Objective: We employed a large-scale pooled analysis to investigate the association of liver cancer-related mortality with being overweight/obese and total cholesterol (TC) levels, since limited and inconsistent data on these associations exist in Japan. Methods: A total of 59,332 participants (23,853 men and 35,479 women) from 12 cohorts without a history of cancer who were followed for a median of 14.3 years were analyzed. A sex-specific stratified Cox proportional hazards model adjusted for age and other potential confounders was used to calculate hazard ratios (HRs) and 95% confidence intervals (CI) for liver cancer-related mortality. Results: A total of 447 participants (266 men and 181 women) died of liver cancer within the follow-up period. Individuals classified as having a high BMI (≥25.0 kg/m2) and low TC levels (<160 mg/dL) had a significantly increased risk for liver cancer-related mortality (HR 7.05, 95% CI 4.41–11.26 in men; HR 8.07, 95% CI 4.76–13.67 in women) when compared with those in the intermediate BMI (18.5–24.9 kg/m2) and TC (160–219 mg/dL) categories. These associations remained after limiting the follow-up duration to >5 years. Conclusion: Being overweight/obese, combined with low TC levels, was strongly associated with liver cancer-related mortality in the EPOCH-JAPAN.

Body mass index and gastrointestinal cancer mortality in Korean adults: A prospective cohort study

BACKGROUND

The association between body mass index (BMI) and mortality from gastrointestinal (GI) cancer remains unclear, especially in Asian populations.

METHODS

A total of 510 148 Korean adults who participated in routine health examinations during the period 2002-2003 were followed up until 2013.

RESULTS

During a mean follow up of 10.5 years, 7831 individuals died of GI cancer. Various associations with BMI were found: U-curve (overall GI, colorectal, liver, and gallbladder cancer), L-curve (stomach cancer), linear (esophageal, extrahepatic bile duct [EBD], and small intestine cancer), and none (pancreatic cancer). Overall GI cancer mortality was lowest at approximately 23.5-26 kg/m2 . For cancers with linear associations, the multivariable adjusted hazard ratios per each 5 kg/m2 higher BMI were 0.53 (95% confidence interval = 0.43-0.65, esophagus), 1.19 (1.02-1.40, EBD), and 0.64 (0.41-0.999, small intestine). For cancers with U-curve or L-curve associations, the corresponding hazard ratios ≥25 kg/m2 were 1.19 (1.08-1.32, overall GI), 1.30 (1.04-1.64, colorectal), 1.28 (1.07-1.53, liver), and 1.30 (0.85-1.97, gallbladder), while in the range of <25 kg/m2 , they were 0.81 (0.76-0.87, overall GI), 0.43 (0.32-0.58, esophagus), 0.70 (0.62-0.79, stomach), and 0.77 (0.65-0.90, colorectal), and these inverse associations did not weaken after excluding the first 7 years of follow up and ever smokers.

CONCLUSIONS

Both low and high BMIs were associated with excess mortality from GI cancers in Korean adults. EBD cancer had a positive association, while esophageal and small intestine cancers had inverse associations. Above 25 kg/m2 , liver and colorectal cancers had positive associations with BMI, whereas below 25 kg/m2 , stomach and colorectal cancers had inverse associations.

Meta-analysis reveals gender difference in the association of liver cancer incidence and excess BMI

Excess body weight has a positive association with risk of liver cancer, but the gender difference in the relationship between body mass index and liver cancer risk remains uncertainty. In this work, we performed meta-analysis for excess body weight and risk of liver cancer incidence to identify the gender difference. We searched the English-languages database and the Chinese literature databases to May 12, 2017. Overall, a total of 17 studies were included. Relative risks (RRs) with 95% confidence intervals was used to evaluate the strength of these associations. The RRs of liver cancer incidence for obese men and women were 2.04 (1.70-2.44) and 1.56 (1.37-1.78). The former one was significantly higher than the later one (P for interaction = 0.02). Notably, the RR of liver cancer incidence in non-Asian obese men was even higher than their counter part (2.31(1.85-2.91) vs. 1.56 (1.31-1.86), P for interaction = 0.01). Similar gender difference was observed in the dose-response curve. As example, at the point of BMI = 32 kg/m², the RRs for men and women were 1.61 (1.45-1.79) and 1.41 (1.02-1.94) respectively. Findings from this meta-analysis indicate that obesity is associated with a higher risk of liver cancer incidence in men, especially in non-Asian men, which might partially contribute to the male dominance of liver cancer incidence.

Obesity and Liver Cancer

Obesity and related metabolic disorders have become globally prevalent posing a challenge for the chronically damaged liver and predisposing the development and progression of cancer. The rising phenomenon of "obesity epidemic" may provide means for understanding why liver cancer is one of the few malignancies with rising incidence in developed countries over the last decades. Non-alcoholic fatty liver disease associated with obesity, insulin resistance, and type 2 diabetes is an increasingly recognized trigger for liver cancer in Western populations characterized by low prevalence of established risk factors for liver cancer such as viral hepatitis and hepatotoxin exposure. Accumulating evidence has established an association between higher body mass index as an indicator of general obesity and higher risk of primary liver cancer. The associations are stronger in men, in patients with underlying liver disease and in white ethnic groups. Abdominal obesity, weight gain in adult life and metabolic factors related to visceral fat accumulation were also suggested as important risk factors for liver cancer; however, more studies are needed to evaluate these associations. The association of obesity and metabolic parameters with liver cancer survival remains controversial. It is unclear which exact mechanisms could provide links between obesity and liver cancer risk. Recent evidence has implicated several molecular pathways in obesity-associated liver cancer. These include insulin resistance leading to increased levels of insulin and insulin-like growth factors, chronic inflammation, adipose tissue remodeling, pro-inflammatory cytokine and adipokine secretion, and altered gut microbiota. These mechanisms coincide with inflammatory and metabolic processes occurring in non-alcoholic fatty liver disease predisposing cancer development and progression. In the context of the current evidence, better understanding of the role of obesity and related metabolic factors may help in improving current strategies for liver cancer prevention.

Ambient air pollution and primary liver cancer incidence in four European cohorts within the ESCAPE project

BACKGROUND

Tobacco smoke exposure increases the risk of cancer in the liver, but little is known about the possible risk associated with exposure to ambient air pollution.

OBJECTIVES

We evaluated the association between residential exposure to air pollution and primary liver cancer incidence.

METHODS

We obtained data from four cohorts with enrolment during 1985-2005 in Denmark, Austria and Italy. Exposure to nitrogen oxides (NO₂ and NO_X), particulate matter (PM) with diameter of less than 10µm (PM₁₀), less than 2.5µm (PM_2.5), between 2.5 and 10µm (PM_2.5-10) and PM_{2.5 absorbance} (soot) at baseline home addresses were estimated using land-use regression models from the ESCAPE project. We also investigated traffic density on the nearest road. We used Cox proportional-hazards models with adjustment for potential confounders for cohort-specific analyses and random-effects meta-analyses to estimate summary hazard ratios (HRs) and 95% confidence intervals (CIs).

RESULTS

Out of 174,770 included participants, 279 liver cancer cases were diagnosed during a mean follow-up of 17 years. In each cohort, HRs above one were observed for all exposures with exception of PM_{2.5 absorbance} and traffic density. In the meta-analysis, all exposures were associated with elevated HRs, but none of the associations reached statistical significance. The summary HR associated with a 10-μg/m³ increase in NO₂ was 1.10 (95% confidence interval (CI): 0.93, 1.30) and 1.34 (95% CI: 0.76, 2.35) for a 5-μg/m³ increase in PM_2.5.

CONCLUSIONS

The results provide suggestive evidence that ambient air pollution may increase the risk of liver cancer. Confidence intervals for associations with NO₂ and NO_X were narrower than for the other exposures.

Adiposity and cancer at major anatomical sites: umbrella review of the literature

Objective To evaluate the strength and validity of the evidence for the association between adiposity and risk of developing or dying from cancer.Design Umbrella review of systematic reviews and meta-analyses.Data sources PubMed, Embase, Cochrane Database of Systematic Reviews, and manual screening of retrieved references.Eligibility criteria Systematic reviews or meta-analyses of observational studies that evaluated the association between indices of adiposity and risk of developing or dying from cancer.Data synthesis Primary analysis focused on cohort studies exploring associations for continuous measures of adiposity. The evidence was graded into strong, highly suggestive, suggestive, or weak after applying criteria that included the statistical significance of the random effects summary estimate and of the largest study in a meta-analysis, the number of cancer cases, heterogeneity between studies, 95% prediction intervals, small study effects, excess significance bias, and sensitivity analysis with credibility ceilings.Results 204 meta-analyses investigated associations between seven indices of adiposity and developing or dying from 36 primary cancers and their subtypes. Of the 95 meta-analyses that included cohort studies and used a continuous scale to measure adiposity, only 12 (13%) associations for nine cancers were supported by strong evidence. An increase in body mass index was associated with a higher risk of developing oesophageal adenocarcinoma; colon and rectal cancer in men; biliary tract system and pancreatic cancer; endometrial cancer in premenopausal women; kidney cancer; and multiple myeloma. Weight gain and waist to hip circumference ratio were associated with higher risks of postmenopausal breast cancer in women who have never used hormone replacement therapy and endometrial cancer, respectively. The increase in the risk of developing cancer for every 5 kg/m2 increase in body mass index ranged from 9% (relative risk 1.09, 95% confidence interval 1.06 to 1.13) for rectal cancer among men to 56% (1.56, 1.34 to 1.81) for biliary tract system cancer. The risk of postmenopausal breast cancer among women who have never used HRT increased by 11% for each 5 kg of weight gain in adulthood (1.11, 1.09 to 1.13), and the risk of endometrial cancer increased by 21% for each 0.1 increase in waist to hip ratio (1.21, 1.13 to 1.29). Five additional associations were supported by strong evidence when categorical measures of adiposity were included: weight gain with colorectal cancer; body mass index with gallbladder, gastric cardia, and ovarian cancer; and multiple myeloma mortality.Conclusions Although the association of adiposity with cancer risk has been extensively studied, associations for only 11 cancers (oesophageal adenocarcinoma, multiple myeloma, and cancers of the gastric cardia, colon, rectum, biliary tract system, pancreas, breast, endometrium, ovary, and kidney) were supported by strong evidence. Other associations could be genuine, but substantial uncertainty remains. Obesity is becoming one of the biggest problems in public health; evidence on the strength of the associated risks may allow finer selection of those at higher risk of cancer, who could be targeted for personalised prevention strategies.

Body Mass Index, Waist Circumference, Diabetes, and Risk of Liver Cancer for U.S. Adults

Incidence rates for liver cancer have increased 3-fold since the mid-1970s in the United States in parallel with increasing trends for obesity and type II diabetes mellitus. We conducted an analysis of baseline body mass index (BMI), waist circumference (WC), and type II diabetes mellitus with risk of liver cancer. The Liver Cancer Pooling Project maintains harmonized data from 1.57 million adults enrolled in 14 U.S.-based prospective studies. Cox regression estimated HRs and 95% confidence intervals (CI) adjusted for age, sex, study center, alcohol, smoking, race, and BMI (for WC and type II diabetes mellitus). Stratified analyses assessed whether the BMI-liver cancer associations differed by hepatitis sera-positivity in nested analyses for a subset of cases (n = 220) and controls (n = 547). After enrollment, 2,162 incident liver cancer diagnoses were identified. BMI, per 5 kg/m2, was associated with higher risks of liver cancer, more so for men (HR = 1.38; 95% CI, 1.30-1.46) than women (HR = 1.25; 95% CI, 1.17-1.35; Pinteraction = 0.02). WC, per 5 cm, was associated with higher risks of liver cancer, approximately equally by sex (overall, HR = 1.08; 95% CI, 1.04-1.13). Type II diabetes mellitus was associated with higher risk of liver cancer (HR = 2.61; 95% CI, 2.34-2.91). In stratified analyses, there was a null association between BMI and liver cancer risk for participants who were sera-positive for hepatitis. This study suggests that high BMI, high WC, and type II diabetes mellitus are associated with higher risks of liver cancer and that the association may differ by status of viral hepatitis infection. Cancer Res; 76(20); 6076-83. ©2016 AACR.

Body mass index, serum total cholesterol, and risk of gastric high-grade dysplasia: A case-control study among Chinese adults

Obesity is related to an increased risk of gastric cardia cancer. However, the influences of excess body weight and serum total cholesterol on the risk of gastric high-grade dysplasia have not been fully characterized.A case-control study was conducted to explore the relationships between body mass index (BMI), serum total cholesterol level, and the risk of gastric high-grade dysplasia in Chinese adults. A total of 893 consecutive patients with gastric high-grade dysplasia (537 men and 356 women) and 902 controls (543 men and 359 women) were enrolled from January 2000 to October 2015. Odds ratios (ORs) with 95% confidence intervals (CIs) were estimated, and a multivariate analysis was conducted.After adjusting for age, alcohol consumption, smoking status, family history of gastric cancer or esophageal cancer, and serum total cholesterol level, a BMI ranging from 27.5 to 29.9 was significantly related to an increased risk of gastric high-grade dysplasia in both men (adjusted OR = 1.87, 95% CI = 1.24-2.81) and women (adjusted OR = 2.72, 95% CI = 1.44-5.16). The 2 highest BMI categories (27.5-29.9 and ≥30.0) were identified as risk factors for gastric cardia high-grade dysplasia in both men (BMI = 27.5-29.9: adjusted OR = 1.78, 95% CI = 1.02-3.10; BMI ≥ 30.0: adjusted OR = 2.54, 95% CI = 1.27-5.08) and women (BMI = 27.5-29.9: adjusted OR = 2.88, 95% CI = 1.27-6.55; BMI ≥ 30.0: adjusted OR = 2.77, 95% CI = 1.36-5.64), whereas only a BMI ranging from 27.5 to 29.9 was a risk factor for gastric noncardia high-grade dysplasia in both men (adjusted OR = 1.98, 95% CI = 1.25-3.14) and women (adjusted OR = 2.88, 95% CI = 1.43-5.81). In addition, higher serum total cholesterol was associated with an increased risk of gastric noncardia high-grade dysplasia (adjusted OR = 1.83, 95% CI = 1.25-2.69) in women.Increased BMI was associated with an increased risk of gastric high-grade dysplasia in both men and women, and higher serum total cholesterol increased the risk of gastric noncardia high-grade dysplasia in women.

European Code against Cancer 4th Edition: Obesity, body fatness and cancer

It is estimated that over half the population of the European Union (EU) is overweight or obese due to an imbalance between energy expenditure and energy intake; this is related to an obesogenic environment of sociocultural, economic and marketing challenges to the control of body weight. Excess body fat is associated with nine cancer sites - oesophagus, colorectum, gall bladder, pancreas, postmenopausal breast, endometrium, ovary, kidney and prostate (advanced) - and 4-38% of these cancers (depending on site and gender) can be attributed to overweight/obesity status. Metabolic alterations which accompany excess body weight are accompanied by increased levels of inflammation, insulin, oestrogens and other hormonal factors. There are some indications that intentional weight loss is associated with reduced cancer incidence (notably in postmenopausal breast and endometrial cancers). Excess body weight is also a risk factor for several other diseases, including diabetes and heart disease, and is related to higher risk of premature death. In reviewing the current evidence related to excess body fat and cancer, the European Code against Cancer Nutrition Working Group has developed the following recommendation: 'Take action to be a healthy body weight'.

The Association Between Body Mass Index and the Prognosis and Postoperative Complications of Hepatocellular Carcinoma: A Meta-Analysis

Previous studies have reported the association between excess body mass index (BMI) and increased risk of hepatocellular carcinoma (HCC). However, whether BMI is associated with the prognosis and postoperative complications of HCC is still not clear.We searched PubMed and Embase for relevant studies published until the date of August 30, 2014. Additional studies were manually identified by searching reference lists of retrieved articles. Pooled hazard ratios (HRs) with 95% confidence intervals (95% CIs) for overall survival (OS), disease-free survival (DFS), and risk ratios (RRs) with 95% CIs for postoperative complications were calculated using random effects or fixed effects models according to heterogeneities between studies.A total of 14 studies were included in the present meta-analysis. The pooled results showed that excess BMI was not significantly associated with improved OS (HR = 0.94; 95% CI: 0.74-1.19, P = 0.588) or DFS (HR = 0.93; 95% CI: 0.79-1.10, P = 0.382). In addition, higher BMI was not associated with increased rate of a number of complications including ascites (RR = 1.25, 95% CI: 0.94-1.65, P = 0.119), bile leaks (RR = 1.22, 95% CI: 0.81-1.83, P = 0.345), and 30-day mortality (RR = 1.05, 95% CI: 0.57-1.96, P = 0.871). However, HCC patients with higher BMI had increased incidence of wound infections (RR = 2.17, 95% CI: 1.28-3.68, P = 0.004).BMI was not an independent prognostic factor for the evaluation of the prognosis in HCC patients, and it was not associated with postoperative complications except for wound infections that as significantly associated with higher BMI scores.

Body fatness as a cause of cancer: epidemiologic clues to biologic mechanisms

Carrying excess body fat is a leading cause of cancer. Epidemiologic evidence gives strong clues about the mechanisms that link excess adiposity to risk for several cancer sites. For postmenopausal breast cancer and endometrial cancer, the hyper-estrogenic state that is induced by excess body fatness is the likely cause. For esophageal cancer and gallbladder cancer, chronic local inflammation induced by acid reflux and gallstones is the likely cause, and for liver cancer, local inflammation induced by hepatic fatty infiltration is the likely cause. However, for several other cancers known to be associated with excess adiposity, including cancers of the colon, pancreas, ovary, kidney, and prostate, specific causes are not known. Possible candidates include elevated systemic or local tissue inflammation induced by adiposity and effects of the elevated levels of leptin, insulin, IGFs, and depressed immune function that are seen with excess adiposity. There is growing evidence that intentional weight loss not only reduces circulating levels of cancer-associated factors but that it also reduces cancer incidence and recurrence. Better research is needed to understand the mechanisms that link excess body fat to cancer risk as well as to understand the amount of weight loss needed for substantial cancer risk reduction. Finally, as we develop better understanding of the mediators of the effects of excess body fatness on cancer risk, we should identify pharmacologic interventions that target those mediators so that they can be used to complement weight loss in order to reduce cancer risk.

Association of body mass index with chromosome damage levels and lung cancer risk among males

Epidemiological studies have shown an etiological link between body mass index (BMI) and cancer risk, but evidence supporting these observations is limited. This study aimed to investigate potential associations of BMI with chromosome damage levels and lung cancer risk. First, we recruited 1333 male workers from a coke-oven plant to examine their chromosome damage levels; and then, a cohort study of 12 052 males was used to investigate the association of BMI with lung cancer incidence. We further carried out a meta-analysis for BMI and male lung cancer risk based on cohort studies. We found that men workers with excess body weight (BMI ≥ 25 kg/m²) had lower levels of MN frequencies than men with normal-weight (BMI: 18.5–24.9). Our cohort study indicated that, the relative risk (RR) for men with BMI ≥ 25 to develop lung cancer was 35% lower than RR for normal-weight men. Further meta-analysis showed that, compared to normal-weight men, men with BMI ≥ 25 had decreased risk of lung cancer among both the East-Asians and others populations. These results indicate that men with excess body weight had significant decreased chromosome damage levels and lower risk of lung cancer than those with normal-weight. However, further biological researches were needed to validate these associations.

Obesity and cancer: the role of vitamin D

Background

It is estimated that 20% of all cancer cases are caused by obesity. Vitamin D is thought to be one of the mechanisms underlying this association. This review aims to summarise the evidence for the mediating effect of vitamin D on the link between obesity and cancer.

Methods

Three literature searches using PubMed and Embase were conducted to assess whether vitamin D plays an important role in the pathway between obesity and cancer: (1) obesity and cancer; (2) obesity and vitamin D; and (3) vitamin D and cancer. A systematic review was performed for (1) and (3), whereas a meta-analysis including random effects analyses was performed for (2).

Results

(1) 32 meta-analyses on obesity and cancer were identified; the majority reported a positive association between obesity and risk of cancer. (2) Our meta-analysis included 12 original studies showing a pooled relative risk of 1.52 (95% CI: 1.33-1.73) for risk of vitamin D deficiency (<50 nmol/L) in obese people (body mass index >30 kg/m²). (3) 21 meta-analyses on circulating vitamin D levels and cancer risk were identified with different results for different types of cancer.

Conclusion

There is consistent evidence for a link between obesity and cancer as well as obesity and low vitamin D. However, it seems like the significance of the mediating role of vitamin D in the biological pathways linking obesity and cancer is low. There is a need for a study including all three components while dealing with bias related to dietary supplements and vitamin D receptor polymorphisms.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2407-14-712) contains supplementary material, which is available to authorized users.

Alcohol and liver cancer: a systematic review and meta-analysis of prospective studies

Despite several studies support a positive association between heavy alcohol consumption and liver cancer risk, a consistent dose-risk relationship has not yet been established. We carried out a systematic review and a meta-analysis of the association between alcohol intake and liver cancer occurrence, following the Meta-analysis Of Observational Studies in Epidemiology guidelines. We searched for cohort and nested case-control studies on the general population published before April 2013, using PubMed and EMBASE. Summary meta-analytic relative risks (RRs) were estimated using random-effect models. We included 16 articles (19 cohorts) for a total of 4445 incident cases and 5550 deaths from liver cancer. Compared with non-drinking, the pooled RRs were 0.91 (95% confidence interval, CI, 0.81-1.02) for moderate drinking (< 3 drinks per day) and 1.16 (95% CI, 1.01-1.34) for heavy drinking (≥ 3 drinks per day), with significant heterogeneity among studies. The dose-risk curve suggested a linear relationship with increasing alcohol intake in drinkers, with estimated excess risk of 46% for 50 g of ethanol per day and 66% for 100 g per day. This systematic review suggests a moderate detrimental role of consumption of 3 or more alcoholic drinks per day on liver cancer, and a lack of association with moderate drinking. Our results have to be taken with due caution on account of the possible limitations of the original studies included in the meta-analysis.