Association between nonalcoholic fatty liver disease and extrahepatic cancers: a systematic review and meta-analysis

Association between metabolic dysfunction-associated steatotic liver disease and risk of colorectal cancer or colorectal adenoma: an updated meta-analysis of cohort studies

Background and aims

In recent years, the relationship between metabolic dysfunction-associated steatotic liver disease (MASLD) and colorectal cancer (CRC) or colorectal adenoma (CRA) has gained widespread attention. Previous meta-analyses on this subject either incorporated numerous cross-sectional studies, which were susceptible to bias, or concentrated solely on a restricted number of cohort studies. Moreover, with the release of a substantial number of high-quality cohort studies on this subject in the past two years, the findings continue to be debated and contradictory. Therefore, we conducted an updated systematic review and meta-analysis of cohort studies to quantitatively evaluate the magnitude of the association between them.

Methods

Comprehensive searches of PubMed, Web of Science, and Embase were conducted without language restrictions from the time of their creation up to December, 2023. The pooled hazard ratios (HRs) with 95% confidence interval (CIs) were calculated by the generic inverse variance based on the random-effects model. Moreover, subgroup and sensitivity analyses were performed.

Results

A total of 15 cohort studies were analyzed in this meta-analysis, which included 9,958,412 participants. The meta-analysis of 13 cohort studies showed that MASLD was linked to a higher risk of CRC (HR=1.25, 95% CI: 1.15-1.36, P < 0.00001). Additionally, further subgroup analysis indicated that the combined HR remained consistent regardless of the study location, nomenclature of fatty liver disease (FLD), confirmation methods for FLD, sample size, follow-up time, and study quality. Furthermore, the meta-analysis of four cohort studies demonstrated that MASLD was correlated with an increased risk of CRA (HR=1.38, 95% CI: 1.17-1.64, P = 0.0002). The sensitivity analysis results further validated the robustness of the aboved findings.

Conclusion

The results of our meta-analysis indicated that MASLD was associated with an increased risk of incident CRC/CRA. In the future, it is necessary to conduct more prospective cohort studies to thoroughly assess potential confounding factors, particularly in individuals from Europe and North America. Furthermore, related mechanism studies should be conducted to enhance our understanding of the link between MASLD and CRC/CRA.

Systematic review registration

Open Science Framework registries (https://osf.io/m3p9k).

Association between non-alcoholic fatty liver disease and the risk of pulmonary nodules in patients with intestinal polyps

Background

Associations between metabolic risk factors and lung cancer remain elusive, and evidence on the linkage between non-alcoholic fatty liver disease (NAFLD) and pulmonary nodules is limited. This study sought to examine the independent association between NAFLD and the risk of pulmonary nodules.

Methods

Cross-sectional analyses of 1,119 patients with intestinal polyps hospitalized at the Department of Gastroenterology, Minhang District Central Hospital of Shanghai, China, were conducted. NAFLD was diagnosed based on hepatic ultrasonography or computed tomography (CT) findings of hepatic steatosis, with exclusion criteria ensuring patients had no history of significant alcohol consumption, viral infections, or hepatic autoimmune diseases. The currently accepted definition of a pulmonary nodule is a solid or sub-solid shadow ≤3 cm in diameter that appears as a solid or semi-solid pattern on a chest CT scan (our specific treatment is pulmonary nodule size: 5 mm to 3 cm). Adjusted 95% confidence intervals (CIs) and odds ratios (ORs) for NAFLD and the clinical features connected with pulmonary nodule risk were determined using a multivariable logistic regression analysis.

Results

Among the 979 intestinal polyp patients, the prevalence rates of NAFLD and pulmonary nodules were 25.9% and 32.8%, respectively. Patients with pulmonary nodules exhibited higher rates of NAFLD (31.5% vs. 23.3%, P=0.006) and obesity (41.4% vs. 32.5%, P=0.006) compared to those without pulmonary nodules. After removing all the possible confounding variables, the adjusted ORs for NAFLD, an older age, smoking, and obesity were 1.370 (95% CI: 1.006-1.867, P=0.04), 1.022 (95% CI: 1.010-1.033), 1.599 (95% CI: 1.033-2.475), and 1.410 (95% CI: 1.057-1.880), respectively (all P values <0.05). NAFLD showed a significant association with an increased risk of pulmonary nodules.

Conclusions

NAFLD was independently linked to an increased incidence of pulmonary nodules in intestinal polyp patients, which emphasizes the importance of screening and managing these conditions in lung cancer prevention.

Association of MASLD with the risk of extrahepatic cancers: A systematic review and meta-analysis of 18 cohort studies

BACKGROUND

Numerous recent studies have explored the association between metabolic dysfunction-associated steatotic liver disease (MASLD) and the risk of various extrahepatic cancers. However, the conclusions were inconclusive. The aim of this study was to clarify this relationship by conducting a robust meta-analysis.

METHODS

Systematic searches were conducted on PubMed, Embase and Web of Science databases to identify relevant cohort studies published prior to February 2024. Hazard ratios (HRs) and their corresponding 95% confidence intervals (95% CIs) were combined using a random-effects model in this meta-analysis.

RESULTS

Eighteen cohort studies (approximately 16.7 million participants) were finally included in this meta-analysis. MASLD was linked to a higher risk of extrahepatic cancers, such as gastric (n = 10, HR = 1.47, 95% CI: 1.07-2.01), colorectal (n = 13, HR = 1.33, 95% CI: 1.16-1.53), pancreatic (n = 8, HR = 1.41, 95% CI: 1.11-1.79), biliary tract (n = 5, HR = 1.27, 95% CI: 1.18-1.37), thyroid (n = 6, HR = 1.46, 95% CI: 1.02-2.09), urinary system (n = 10, HR = 1.45, 95% CI: 1.25-1.69), breast (n = 11, HR = 1.17, 95% CI: 1.08-1.26) and female genital organ cancers (n = 10, HR = 1.36, 95% CI: 1.11-1.66). However, there was no statistically significant association between MASLD and the risk of head and neck (n = 6, HR = 1.03, 95% CI: 99-1.07), oesophageal (n = 9, HR = 1.26, 95% CI: 0.86-1.86), lung (n = 9, HR = 1.01, 95% CI: 0.92-1.10), prostate (n = 9, HR = 1.06, 95% CI: 0.94-1.19) or small intestine cancer (n = 2, HR = 1.75, 95% CI: 1.00-3.06).

CONCLUSIONS

This latest large-scale meta-analysis indicated that MASLD was associated with an increased risk of various extrahepatic cancers, such as gastric, colorectal, pancreatic, biliary duct, thyroid, urinary system, breast, skin and female genital cancers. Further research is needed to investigate the mechanisms underlying these associations.

NON-ALCOHOLIC FATTY LIVER DISEASE AND EXTRA-HEPATIC CANCER: A NARRATIVE REVIEW

BACKGROUND

Recently, significant associations between non-alcoholic fatty liver disease (NAFLD) and extra-hepatic cancer have been reported.

OBJECTIVE

To carry out a comprehensive review of the current evidence in the literature on the association between NAFLD and extra-hepatic cancer.

METHODS

A narrative literature review was performed through an online search for the MeSH terms "fatty liver" and "cancer" in MEDLINE (via PubMed) and LILACS (via BVS). Original studies that described the impact of NAFLD on different types of extra-hepatic malignancies were included.

RESULTS

After careful analysis, nine prospective cohort studies, one retrospective cohort study, three case-control studies, and three cross-sectional studies were selected.

CONCLUSION

There is consistent evidence on the association between NAFLD and extra-hepatic carcinogenesis, especially in relation to colorectal, gastric, pancreatic, breast, prostate, and bladder cancers.

Utility of Alpha-Fetoprotein and Ultrasound in the Diagnosis and Prognosis of Patients with Hepatocellular Liver Cancer

Objective

To investigate the utility of alpha-fetoprotein (AFP) and ultrasound in the diagnosis and prognosis of patients with hepatocellular liver cancer (HCC).

Methods

Using retrospective convenience sampling, 401 patients with HCC who underwent transarterial chemoembolisation at the Department of Oncology of The Affiliated Huaian No.1 People's Hospital of Nanjing Medical University between June 2015 and January 2020 were recruited and assigned to the case group. Simultaneously, patients matched to the case group in terms of gender and age but excluded for HCC were enrolled at a 1:1 ratio and classified as the control group. Relevant parameters were collected from both groups for comparison.

Results

Both AFP levels and ultrasound results demonstrated diagnostic value for patients with HCC (P < 0.05). Their combined use exhibited the highest diagnostic accuracy for the cancer, with an area under the curve of 0.896 (95% confidence interval [CI]: 0.876, 0.923), a sensitivity of 67.65% and a specificity of 91.22%. In terms of overall survival (OS), statistically significant differences in the OS rates were observed between the low-AFP (L-AFP) group and high-AFP (H-AFP) group as well as between the low-tumour-diameter (LTD) group and high-tumour-diameter (HTD) group (81.31% vs 52.22% and 85.11% vs 63.41%, respectively; P < 0.05). Regarding the progression-free survival (PFS), significant differences in the PFS rates were also noted between the L-AFP and H-AFP groups and between the LTD and HTD groups (81.31% vs 52.22% and 85.11% vs 63.41%, respectively; P < 0.05).

Conclusion

Ultrasound and AFP display notable distinctions when used in the diagnosis of HCC. The sensitivity of ultrasound as a standalone diagnostic tool surpasses that of AFP alone. However, their combined use results in much higher specificity than the use of either test individually. In addition, both techniques hold predictive value for patients' OS and PFS, enabling timely prognostic assessment.

Unveiling the cancer risk nexus of the steatotic liver

Steatotic liver, characterized by the accumulation of fat in the liver, poses significant health risks including metabolic dysfunction-associated steatotic liver disease (MASLD) and an elevated risk of primary liver cancer. Emerging evidence indicates a robust association between steatotic liver and increased susceptibility to extrahepatic primary cancers and their metastases. The deposition of fat induces dynamic changes in hepatic microenvironments, thereby fostering inflammation and immune responses that enhance liver metastasis from extrahepatic primary cancers. This review explores the impact of steatotic liver on hepatic carcinogenesis and metastasis from extrahepatic cancers, with a specific focus on hepatocyte-derived factors and the immune microenvironment. By emphasizing novel conclusions, this article underscores the timely relevance of understanding these intricate connections.

Association between metabolic dysfunction-associated steatotic liver disease and risk of incident pancreatic cancer: a systematic review and meta-analysis of cohort studies

Background and objectives

Since the results of previous observational studies on the relationship between metabolic dysfunction-associated steatotic liver disease (MASLD) and pancreatic cancer were still controversial and inconsistent, we performed a systematic evaluation and meta-analysis of cohort studies to assess any potential association.

Methods

We conducted a systematic search of PubMed, Embase, and Web of Science databases from the database's inception up to November 30, 2023. For summary purposes, hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated using random-effects models, and subgroup and sensitivity analyses were performed as well. The Egger's test and Begg's test were utilized to detect the publication bias.

Results

This meta-analysis included nine cohort studies with a total of 10,428,926 participants. The meta-analysis demonstrated an increased risk of pancreatic cancer in those with MASLD (HR = 1.32, 95% CI: 1.10-1.59, P = 0.003) with moderate heterogeneity (I2 = 54%, P = 0.03). Subsequent subgroup analyses revealed that the pooled HRs remained significantly unchanged, irrespective of the study area, nomenclature of fatty liver disease, and sample size. The results of the sensitivity analyses remained unchanged. No evidence of publication bias was found.

Conclusion

This meta-analysis indicated that MASLD was associated with a higher risk of pancreatic cancer. To further strengthen the association, future prospective cohort studies should take into account different ethnic groups, diagnostic methods of fatty liver, the severity of MASLD, and potential confounding factors, as well as explore the potential mechanisms of pancreatic cancer development in MASLD patients.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier: CRD42023489137.

Development and validation of a clinical prediction model for the risk of distal metastasis in intrahepatic cholangiocarcinoma: a real-world study

BACKGROUND

Cholangiocarcinoma (CCA) is a highly malignant and easily metastatic bile duct tumor with poor prognosis. We aimed at studying the associated risk factors affecting distal metastasis of CCA and using nomogram to guide clinicians in predicting distal metastasis of CCA.

METHODS

Based on inclusion and exclusion criteria, 345 patients with CCA were selected from the Fifth Medical Center of Chinese PLA General Hospital and were divided into distal metastases (N = 21) and non-distal metastases (N = 324). LASSO regression models were used to screen for relevant parameters and to compare basic clinical information between the two groups of patients. Risk factors for distal metastasis were identified based on the results of univariate and multivariate logistic regression analyses. The nomogram was established based on the results of multivariate logistic regression, and we drawn the corresponding correlation heat map. The predictive accuracy of the nomogram was evaluated by receiver operating characteristic (ROC) curves and calibration plots. The utility of the model in clinical applications was illustrated by applying decision curve analysis (DCA), and overall survival(OS) analysis was performed using the method of Kaplan-meier.

RESULTS

This study identified 4 independent risk factors for distal metastasis of CCA, including CA199, cholesterol, hypertension and margin invasion, and developed the nomogram based on this. The result of validation showed that the model had significant accuracy for diagnosis with the area under ROC (AUC) of 0.882 (95% CI: 0.843-0.914). Calibration plots and DCA showed that the model had high clinical utility.

CONCLUSIONS

This study established and validated a model of nomogram for predicting distal metastasis in patients with CCA. Based on this, it could guide clinicians to make better decisions and provide more accurate prognosis and treatment for patients with CCA.

Associations between metabolic dysfunction-associated fatty liver disease and extrahepatic cancers: a cohort in China

Background

To evaluate the associations between a new definition of metabolic dysfunction-associated fatty liver disease (MAFLD) and extrahepatic cancers and compare with nonalcoholic fatty liver disease (NAFLD).

Methods

We enrolled 151,391 Chinese participants in the Kailuan cohort. Hepatic steatosis was detected by abdominal ultrasound. Fine and Gray competing risk regression models were used to estimate hazard ratios (HRs) and 95% confidence interval (CI) between MAFLD and extrahepatic cancers.

Results

MAFLD was associated with increased risk of prostate (HR =1.49, 95% CI: 1.07-2.08) and obesity-related cancers, including thyroid (HR =1.47, 95% CI: 1.01-2.12), kidney (HR =1.54, 95% CI: 1.18-2.00), colorectal (HR =1.15, 95% CI: 0.98-1.34) and breast cancer (HR =1.31, 95% CI: 1.04-1.66). The results were consistent in NAFLD vs. non-NAFLD and MAFLD-NAFLD vs. neither FLD. Compared with the neither FLD group, the NAFLD-only group had a higher risk of extrahepatic cancers (HR =1.57, 95% CI: 1.18-2.09), esophageal (HR =5.11, 95% CI: 2.25-11.62), and bladder cancer (HR =3.36, 95% CI: 1.23-9.17). The additional risk of extrahepatic cancers (HR =1.42, 95% CI: 1.17-1.73), esophageal (HR =4.37, 95% CI: 2.55-7.49), and breast cancer (HR =1.99, 95% CI: 1.01-3.92) was observed in MAFLD with metabolic dysregulation, and kidney (HR =1.83, 95% CI: 1.38-2.43), prostate (HR =1.46, 95% CI: 1.00-2.14) and breast cancer (HR =1.33, 95% CI: 1.02-1.74) was observed in MAFLD with overweight and metabolic dysregulation, as well as colorectal (HR =1.45, 95% CI: 1.07-1.96) and prostate cancer (HR =2.44, 95% CI: 1.42-4.21) in MAFLD with three risk factors. Additionally, MAFLD with excessive alcohol consumption would increase extrahepatic cancers (HR =1.14, 95% CI: 1.01-1.29) and breast cancer (HR =7.27, 95% CI: 2.33-22.69) risk.

Conclusions

MAFLD and NAFLD shared similar excessive risks of obesity-related cancers, suggesting a driving role of FLD in these cancers. Metabolic dysregulation beyond obesity may play additional kidney, colorectal, and prostate cancer risks in MAFLD patients. It may be helpful in the clinic to relieve symptoms by treating metabolic disorders and preventing adverse outcomes of extrahepatic cancers.

2022 Update on Prostate Cancer Epidemiology and Risk Factors-A Systematic Review

CONTEXT

Prostate cancer (PCa) is one of the most common cancers worldwide. Understanding the epidemiology and risk factors of the disease is paramount to improve primary and secondary prevention strategies.

OBJECTIVE

To systematically review and summarize the current evidence on the descriptive epidemiology, large screening studies, diagnostic techniques, and risk factors of PCa.

EVIDENCE ACQUISITION

PCa incidence and mortality rates for 2020 were obtained from the GLOBOCAN database of the International Agency for Research on Cancer. A systematic search was performed in July 2022 using PubMed/MEDLINE and EMBASE biomedical databases. The review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines and was registered in PROSPERO (CRD42022359728).

EVIDENCE SYNTHESIS

Globally, PCa is the second most common cancer, with the highest incidence in North and South America, Europe, Australia, and the Caribbean. Risk factors include age, family history, and genetic predisposition. Additional factors may include smoking, diet, physical activity, specific medications, and occupational factors. As PCa screening has become more accepted, newer approaches such as magnetic resonance imaging (MRI) and biomarkers have been implemented to identify patients who are likely to harbor significant tumors. Limitations of this review include the evidence being derived from meta-analyses of mostly retrospective studies.

CONCLUSIONS

PCa remains the second most common cancer among men worldwide. PCa screening is gaining acceptance and will likely reduce PCa mortality at the cost of overdiagnosis and overtreatment. Increasing use of MRI and biomarkers for the detection of PCa may mitigate some of the negative consequences of screening.

PATIENT SUMMARY

Prostate cancer (PCa) remains the second most common cancer among men, and screening for PCa is likely to increase in the future. Improved diagnostic techniques can help reduce the number of men who need to be diagnosed and treated to save one life. Avoidable risk factors for PCa may include factors such as smoking, diet, physical activity, specific medications, and certain occupations.

The Global Prevalence of Nonalcoholic Fatty Liver Disease and its Association With Cancers: Systematic Review and Meta-Analysis

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is one of the common causes of chronic liver disease globally. Obesity, metabolic diseases, and exposure to some environmental agents contribute to NAFLD. NAFLD is commonly considered a precursor for some types of cancers. Since the leading causes of death in people with NAFLD are cardiovascular disease and extrahepatic cancers, it is important to understand the mechanisms of the progression of NAFLD to control its progression and identify its association with extrahepatic cancers. Thus, this review aims to estimate the global prevalence of NAFLD in association with the risk of extrahepatic cancers.

OBJECTIVE

We aimed to determine the prevalence of various cancers in NAFLD patients and the association between NAFLD and cancer.

METHODS

We searched PubMed, ProQuest, Scopus, and Web of Science from database inception to March 2022 to identify eligible studies reporting the prevalence of NAFLD and the risk of incident cancers among adult individuals (aged ≥18 years). Data from selected studies were extracted, and meta-analysis was performed using random effects models to obtain the pooled prevalence with the 95% CI. The quality of the evidence was assessed with the Newcastle-Ottawa Scale.

RESULTS

We identified 11 studies that met our inclusion criteria, involving 222,523 adults and 3 types of cancer: hepatocellular carcinoma (HCC), breast cancer, and other types of extrahepatic cancer. The overall pooled prevalence of NAFLD and cancer was 26% (95% CI 16%-35%), while 25% of people had NAFLD and HCC (95% CI 7%-42%). NAFLD and breast cancer had the highest prevalence out of the 3 forms of cancer at 30% (95% CI 14%-45%), while the pooled prevalence for NAFLD and other cancers was 21% (95% CI 12%-31%).

CONCLUSIONS

The review suggests that people with NAFLD may be at an increased risk of cancer that might not affect not only the liver but also other organs, such as the breast and bile duct. The findings serve as important evidence for policymakers to evaluate and recommend measures to reduce the prevalence of NAFLD through lifestyle and environmental preventive approaches.

TRIAL REGISTRATION

PROSPERO CRD42022321946; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=321946.

Extrahepatic Outcomes of Nonalcoholic Fatty Liver Disease: Nonhepatocellular Cancers

Nonalcoholic fatty liver disease (NAFLD) encompasses the entire spectrum of fatty liver disease in individuals without significant alcohol consumption, including isolated steatosis, steatohepatitis, and cirrhosis. The overall global prevalence of NAFLD is estimated to be 30%, and the associated clinical and economic burden will continue to increase. NAFLD is a multisystemic disease with established links to cardiovascular disease, type 2 diabetes, metabolic syndrome, chronic kidney disease, polycystic ovarian syndrome, and intra- and extrahepatic malignancies. In this article the authors review the potential mechanisms and current evidence for the association between NAFLD and extrahepatic cancers and the resultant impact on clinical outcomes.

From NAFLD to MAFLD: Definition, Pathophysiological Basis and Cardiovascular Implications

Non-alcoholic fatty liver disease (NAFLD) is defined as a chronic liver disease characterized by excessive fat accumulation in the liver without another obvious cause (no excessive alcohol consumption, hepatotoxic medications, toxins, viral infections, genetic hepatic diseases), therefore it is an exclusion diagnosis. The term NAFLD literally refers to non-alcohol related hepatopathy and does not adequately correlate with metabolic dysfunction and related cardiovascular risks. Therefore, researchers and scientific societies have moved towards changing the terminology. The novel nomenclature for a metabolic-associated fatty liver disease (MAFLD) has been proposed in 2020 by a group of experts to overcome the issues related to the old terminology. The diagnosis of MAFLD is based on the presence of hepatic steatosis and at least one between these three conditions: type 2 diabetes mellitus (T2DM), obesity or metabolic dysregulation. MAFLD has been shown to be an independent risk factor for cardiovascular diseases and atherosclerosis. It is better related to the main risk factors for atherosclerosis and cardiovascular diseases than NAFLD, such as dyslipidemia, T2DM and hypertension. The aim of this review is to highlight the reasons why the term NAFLD is moving to the term MAFLD, what are the conceptual basis of this choice and its clinical implications, particularly in the cardiovascular field.

Fatty Liver and Risk of Head and Neck Cancer in Type 2 Diabetes Mellitus: A Nationwide Cohort Study

This study is aimed at investigating the association between NAFLD and the risk of HNC separately based on cancer site using a large population-based cohort of patients with T2DM. The data used in this population-based retrospective cohort study were provided by the Korean National Health Insurance Service. The Cox proportional hazards model was used to estimate multivariable adjusted hazard ratios and 95% CIs for the association of the fatty liver index (FLI) and the risk of HNC. During the mean 6.9 years of follow-up, approximately 25.4% of the study cohort had NAFLD, defined as an FLI ≥60. A total of 3543 HNC cases were identified. Overall, patients with a higher FLI had a significantly higher risk of HNC in the oral cavity, pharynx, and larynx compared with patients with an FLI <30. An association was not observed between salivary gland cancer and FLI. There was no association between obesity and HNC. However, obese patients showed a lower risk of cancer for the oral cavity (p = 0.040), pharynx (p = 0.009), and larynx (p < 0.001) than non-obese patients with the same FLI level. Neither obesity nor smoking affected the association between FLI- and HNC-risk in stratified analyses. In T2DM patients, NAFLD was associated with an increased risk of developing HNC in the oral cavity, pharynx, and larynx, but not in the salivary gland.

Nonalcoholic fatty liver disease and non-liver comorbidities

Non-alcoholic fatty liver disease (NAFLD) is a chronic liver disease characterized by excess fat accumulation in the liver. It is closely associated with metabolic syndrome, and patients with NAFLD often have comorbidities such as obesity, type 2 diabetes mellitus, and dyslipidemia. In addition to liver-related complications, NAFLD has been associated with a range of non-liver comorbidities, including cardiovascular disease, chronic kidney disease, and sleep apnea. Cardiovascular disease is the most common cause of mortality in patients with NAFLD, and patients with NAFLD have a higher risk of developing cardiovascular disease than the general population. Chronic kidney disease is also more common in patients with NAFLD, and the severity of NAFLD is associated with a higher risk of developing chronic kidney disease. Sleep apnea, a disorder characterized by breathing interruptions during sleep, is also more common in patients with NAFLD and is associated with the severity of NAFLD. The presence of non-liver comorbidities in patients with NAFLD has important implications for the management of this disease. Treatment of comorbidities such as obesity, type 2 diabetes mellitus, and dyslipidemia may improve liver-related outcomes in patients with NAFLD. Moreover, treatment of non-liver comorbidities may also improve overall health outcomes in patients with NAFLD. Therefore, clinicians should be aware of the potential for non-liver comorbidities in patients with NAFLD and should consider the management of these comorbidities as part of the overall management of this disease.

Risk factors for gastric cancer: A comprehensive analysis of observational studies

Background

Multifarious factors have a causal relationship with gastric cancer (GC) development. We conducted a comprehensive analysis to evaluate the strength of the evidence examining non-genetic risk factors for gastric cancer.

Methods

PubMed, Web of Science, and the Cochrane Library were searched from inception to November 10, 2021 to identify meta-analyses of observational studies examining the association between environmental factors and GC risk. For each meta-analysis, the random effect size, 95% confidence interval, heterogeneity among studies, and evidence of publication bias were assessed; moreover, the evidence was graded using predefined criteria, and the methodological quality was evaluated using AMSTAR 2.

Results

A total of 137 associations were examined in 76 articles. Among these meta-analyses, 93 associations yielded significant estimates (p < 0.05). Only 10 associations had strong epidemiologic evidence, including 2 risk factors (waist circumference and bacon), and 8 protective factors (dietary total antioxidant capacity, vegetable fat, cruciferous vegetable, cabbage, total vitamin, vitamin A, vitamin C, and years of fertility); 26 associations had moderate quality of evidence; and the remaining 57 associations were rated as weak. Ninety-four (68.61%) associations showed significant heterogeneity. Twenty-five (18.25%) associations demonstrated publication bias.

Conclusions

In this comprehensive analysis, multiple associations were found between environmental factors and GC with varying levels of evidence. Healthy dietary habits and lifestyle patterns could reduce the risk for GC. However, further high-quality prospective studies are still necessary to draw more definitive conclusions.

Factors associated with the development of extrahepatic malignancy in patients with nonalcoholic fatty liver disease: a single-center longitudinal study

BACKGROUND AND AIMS

The aim of the present study was to determine incident cases of extrahepatic malignancy in patients with nonalcoholic fatty liver disease (NAFLD) and to identify whether the factors are associated with cancer development.

METHODS

Between 15 January 2001 and 14 March 2021, a total of 1365 patients had been diagnosed with NAFLD were enrolled in the study.

RESULTS

The median follow-up period was 59.5 months. The mean age was 50.9 ± 10.9 years. The female gender was predominant (57%). During the follow-up period, 62 extrahepatic malignancies and 11 hepatocellular carcinomas were identified. Of all extrahepatic malignancies, 51 were solid organ malignancies and 11 were hematological malignancies. Female breast cancer was the most frequent (25.8%), followed by thyroid cancer (19.4%), lymphoma (12.9%), and lung cancer (9.7%). In univariate and multivariable analyses, after adjusting for age and sex, the presence of diabetes and high initial baseline gamma glutamyl transpeptidase (GGT) levels were significantly associated with the development of extrahepatic malignancies [hazard ratio (HR) = 1.82, 95% confidence interval (CI): 1.04-3.20, P = 0.036] and HR = 1.96, 95% CI: 1.14-3.38, P = 0.015, respectively). In 424 biopsy-proven NAFLD patients, the development of extrahepatic cancer was significantly associated with the severity of hepatic fibrosis (HR = 3.31, 95% CI: 1.36-8.07; P = 0.008).

CONCLUSION

Extrahepatic malignancies are frequently seen in patients with NAFLD. Diabetes mellitus, high baseline GGT levels, and significant hepatic fibrosis are associated with the development of extrahepatic cancer in patients with NAFLD.

The impact of hepatic steatosis on outcomes of colorectal cancer patients with liver metastases: A systematic review and meta-analysis

Background

It is unclear how hepatic steatosis impacts patient prognosis in the case of colorectal cancer with liver metastases (CRLM). The purpose of this review was to assess the effect of hepatic steatosis on patient survival and disease-free survival (DFS) in the case of CRLM.

Methods

We examined the databases of PubMed, CENTRAL, Embase, Google Scholar, and ScienceDirect for studies reporting outcomes of CRLM patients with and without hepatic steatosis. We performed a random-effects meta-analysis using multivariable adjusted hazard ratios (HR).

Results

Nine studies reporting data of a total of 14,197 patients were included. All patients had undergone surgical intervention. Pooled analysis of seven studies indicated that hepatic steatosis had no statistically significant impact on patient survival in CRLM (HR: 0.92 95% CI: 0.82, 1.04, I² = 82%, p = 0.18). Specifically, we noted that there was a statistically significant improvement in cancer-specific survival amongst patients with hepatic steatosis (two studies; HR: 0.85 95% CI: 0.76, 0.95, I² = 41%, p = 0.005) while there was no difference in overall survival (five studies; HR: 0.97 95% CI: 0.83, 1.13, I² = 78%, p = 0.68). On meta-analysis of four studies, we noted that the presence of hepatic steatosis resulted in statistically significant reduced DFS in patients with CRLM (HR: 1.32 95% CI: 1.08, 1.62, I² = 67%, p = 0.007).

Conclusion

The presence of hepatic steatosis may not influence patient survival in CRLM. However, scarce data is suggestive of poor DFS in CRLM patients with hepatic steatosis. Further prospective studies taking into account different confounding variables are needed to better assess the effect of hepatic steatosis on outcomes of CRLM.

Systematic review registration

[https://www.crd.york.ac.uk/prospero/#searchadvanced], identifier [CRD42022320665].

Hepatocellular and extrahepatic cancers in non-alcoholic fatty liver disease: A systematic review and meta-analysis

BACKGROUND

Hepatocellular (HCC) and extrahepatic cancers have been associated with non-alcoholic fatty liver disease (NAFLD); however, the extent and nature of these relationships remain unclear. We aimed to estimate the absolute incidence rates of these cancers in adults with NAFLD with respect to key demographic and clinical factors.

METHODS

We searched PubMed, Embase, Cochrane Library and Web of Science databases for studies reporting the incidence rates of any cancer in adults with NAFLD from inception to 31 August 2020. The main meta-analysis outcomes were pooled incidences of cancers in NAFLD using random-effects modelling. Subgroup analyses examined the effects of NAFLD disease stage.

FINDINGS

In total, 64 studies were eligible for analysis of HCC and extrahepatic cancer incidence including 625,984 and 41,027 patients, respectively. The pooled HCC incidence rate was 1.25 per 1000 person-years (95% CI 1.01 to 1.49; I² = 94.8%). In patients with NAFLD with advanced liver fibrosis or cirrhosis, the HCC incidence rate was 14.46 per 1000 person-years (95% CI 10.89 to 18.04; I² = 91.3%). The pooled extrahepatic cancer incidence rate was 10.58 per 1000 person-years (95% CI 8.14 to 13.02; I² = 97.1%). The most frequently occurring extrahepatic cancers were uterine, breast, prostate, colorectal, and lung. Extrahepatic cancer incidence rates were not higher in patients with NAFLD with advanced liver fibrosis or cirrhosis.

INTERPRETATION

The rate of HCC development in patients with NAFLD who have progressed to advanced liver fibrosis or cirrhosis supports current HCC surveillance recommendations targeted for this group. Extrahepatic cancers are over eight-fold more frequent than HCC in NAFLD and not associated with liver fibrosis stage. As the global prevalence of NAFLD is approximately 25% and increasing, these findings support a focus on its prevention and the early detection of cancer in adults with NAFLD.

Metabolically associated fatty liver disease – a disease of the 21st century: A review

Metabolically associated fatty liver disease (MAFLD) is a widespread chronic disease characterized by increased accumulation of fat in the liver, which is based on metabolic dysfunction. The incidence of MAFLD is well over 20% in most regions of the world and is on an increasing trend. Current thinking considers the etiology and pathogenesis of MAFLD under the concept of "multiple parallel blows". According to this model, the development and progression of the disease are due to the interaction of multiple genetic, environmental and adaptive factors, which include specific genetic polymorphisms (e.g., the PNPLA3 gene) and epigenetic modifications, dietary patterns (e.g. high saturated fat and fructose intake), sedentary activity, obesity, insulin resistance, dysregulation of adipokines, lipotoxicity, oxidative stress, and gut microbiota dysbiosis (small intestinal bacterial overgrowth syndrome). The basis for the diagnosis of MAFLD is the presence of proven hepatic steatosis in combination with one of the following criteria: overweight/obesity, presence of type 2 diabetes mellitus, signs of metabolic dysregulation. Nonmedicamental therapies recommended for patients with MAFLD include weight loss (if overweight or obese), reduction of saturated fatty acid and fructose intake, and inclusion of adequate amounts of omega-3 polyunsaturated fatty acids and dietary fibre (psyllium) in the diet. Pharmacotherapy of MAFLD should be aimed at correcting insulin resistance, improving liver function and reducing the risk of associated diseases.

Non-Alcoholic Fatty Liver Disease and Extrahepatic Cancers: A Wolf in Sheep’s Clothing?

Non-alcoholic fatty liver disease (NAFLD) is now considered the main driver and leading cause of chronic liver disease globally. The umbrella term NAFLD describes a range of liver conditions closely related to insulin resistance, metabolic syndrome, diabetes mellitus, obesity, and dyslipidemia. At the same time, several malignancies, including hepatocellular carcinoma and colorectal cancer, are considered to be common causes of death among patients with NAFLD. At first, our review herein aims to investigate the role of NAFLD in developing colorectal neoplasms and adenomatous polyps based on the current literature. We will also explore the connection and the missing links between NAFLD and extrahepatic cancers. Interestingly, any relationship between NAFLD and extrahepatic malignancies could be attributable to several shared metabolic risk factors. Overall, obesity, insulin resistance, metabolic syndrome, and related disorders may increase the risk of developing cancer. Therefore, early diagnosis of NAFLD is essential for preventing the progression of the disease and avoiding its severe complications. In addition, cancer screening and early detection in these patients may improve survival and reduce any delays in treatment.

Current therapies and new developments in NASH

Non-alcoholic steatohepatitis is becoming the most important aetiology for advanced liver disease. There has been important progress in the field in recent years and the complexity of the pathophysiology of NASH is better understood. Multiple non-invasive circulating and imaging biomarkers have been tested. The importance of lifestyle has been recognised and several drugs are being tested in clinical trials. This review addresses the challenges that healthcare professionals face in the management of NASH patients.

Nonalcoholic fatty liver disease and health outcomes: An umbrella review of systematic reviews and meta-analyses

Purpose:

A large number of systemic reviews and meta-analyses have explored the relationship between nonalcoholic fatty liver disease (NAFLD) and multiple health outcomes. The aim of this study is to conduct an umbrella review to assess the strength and evidence for the association between NAFLD and health outcomes.

Methods:

We systematically identified the present meta-analyses of observational studies reporting an association between NAFLD and health outcomes. For each meta-analysis, we assessed the quality with AMSTAR2 and graded the epidemiologic evidence.

Results:

Fifty-four articles comprising 111 unique meta-analyses were included in this study. Eighty-five unique outcomes showed significant associations ( P ← 0.05), whereas 26 unique outcomes showed insignificant associations, and we cannot assess the epidemiologic evidence. For 85 significant health outcomes, four outcomes (carotid intima-media thickness (C-IMT), peak A velocity, left ventricle end-diastolic diameter, incident chronic kidney disease (CKD) in adult patients) was graded as high quality of evidence, 23 outcomes were graded as the moderate quality of evidence, and the remaining 58 outcomes were graded as weak quality of evidence. Fourty-seven (87.03%) studies showed critically low methodological quality.

Conclusion:

In this umbrella review, only four statistically significant health outcomes showed high epidemiologic evidence. NAFLD seems to relate to an increased risk of C-IMT, peak A velocity, left ventricle end-diastolic diameter, and incident CKD in adult patients.

Metabolic-associated Fatty Liver Disease (MAFLD): A Multi-systemic Disease Beyond the Liver

Nonalcoholic fatty liver disease (NAFLD) is a multisystemic clinical condition that presents with a wide spectrum of extrahepatic manifestations, such as obesity, type 2 diabetes mellitus, metabolic syndrome, cardiovascular diseases, chronic kidney disease, extrahepatic malignancies, cognitive disorders, and polycystic ovarian syndrome. Among NAFLD patients, the most common mortality etiology is cardiovascular disorders, followed by extrahepatic malignancies, diabetes mellitus, and liver-related complications. Furthermore, the severity of extrahepatic diseases is parallel to the severity of NAFLD. In clinical practice, awareness of the associations of concomitant diseases is of major importance for initiating prompt and timely screening and multidisciplinary management of the disease spectrum. In 2020, a consensus from 22 countries redefined the disease as metabolic (dysfunction)-associated fatty liver disease (MAFLD), which resulted in the redefinition of the corresponding population. Although the patients diagnosed with MAFLD and NAFLD mostly overlap, the MAFLD and NAFLD populations are not identical. In this review, we compared the associations of key extrahepatic diseases between NAFLD and MAFLD.

Risk of hepatic and extrahepatic cancer in NAFLD: A population-based cohort study

BACKGROUND AND AIMS

Individuals with non-alcoholic fatty liver disease (NAFLD) may be at greater risk of cancer. This study aimed to investigate the risk of hepatic and extrahepatic cancer compared to the general population in a population-based cohort of patients with NAFLD.

METHODS

We used the Swedish National Patient Registry from 1987 to 2016 to identify patients with a NAFLD diagnosis and no prior cancer. All patients with NAFLD were compared to up to 10 controls matched for age, sex and living location. The primary outcome was the first occurrence of any cancer as ascertained from national registries. As secondary outcomes, we analysed the risk of pre-specified cancer subtypes. Cox regression models, adjusted for baseline diabetes, hypertension, hyperlipidaemia and chronic obstructive pulmonary disease were applied.

RESULTS

We identified 8415 patients with NAFLD. Over a median follow-up of 6.0 years (IQR 2.5-11.2 years), an increased risk for any cancer was found in patients with NAFLD compared to controls (9.7 vs. 8.6 cases per 1000 person-years): hazard ratio (HR) = 1.22 (95% confidence interval, CI = 1.12-1.33). The risk for hepatocellular carcinoma (HCC) was particularly high (adjusted HR, aHR = 12.18, 95% CI = 7.15-20.79). The risk for some other cancer subtypes increased (colorectal [aHR 1.38], kidney [aHR 2.12], bladder [aHR 2.51] and uterine [aHR 1.78]), but was low in absolute terms.

CONCLUSION

In this population-based cohort, NAFLD was associated with an increased risk of developing cancer (especially HCC). The absolute risk for other forms of cancer was generally comparable to the control population.

Non-alcoholic fatty liver disease and increased risk of incident extrahepatic cancers: a meta-analysis of observational cohort studies

OBJECTIVE

We performed a meta-analysis of observational studies to quantify the magnitude of the association between non-alcoholic fatty liver disease (NAFLD) and risk of extrahepatic cancers.

DESIGN

We systematically searched PubMed, Scopus and Web of Science databases from the inception date to 30 December 2020 using predefined keywords to identify observational cohort studies conducted in individuals, in which NAFLD was diagnosed by imaging techniques or International Classification of Diseases codes. No studies with biopsy-proven NAFLD were available for the analysis. Meta-analysis was performed using random-effects modelling.

RESULTS

We included 10 cohort studies with 182 202 middle-aged individuals (24.8% with NAFLD) and 8485 incident cases of extrahepatic cancers at different sites over a median follow-up of 5.8 years. NAFLD was significantly associated with a nearly 1.5-fold to twofold increased risk of developing GI cancers (oesophagus, stomach, pancreas or colorectal cancers). Furthermore, NAFLD was associated with an approximately 1.2-fold to 1.5-fold increased risk of developing lung, breast, gynaecological or urinary system cancers. All risks were independent of age, sex, smoking, obesity, diabetes or other potential confounders. The overall heterogeneity for most of the primary pooled analyses was relatively low. Sensitivity analyses did not alter these findings. Funnel plots did not reveal any significant publication bias.

CONCLUSION

This large meta-analysis suggests that NAFLD is associated with a moderately increased long-term risk of developing extrahepatic cancers over a median of nearly 6 years (especially GI cancers, breast cancer and gynaecological cancers). Further research is required to decipher the complex link between NAFLD and cancer development.

Circulating chemerin levels in metabolic-associated fatty liver disease: a systematic review and meta-analysis

Background and objectives

Chemerin is a brand-new adipokine that has been linked to both inflammation and metabolic dysfunction. Even though a rising number of studies have connected chemerin to metabolic-associated fatty liver disease (MAFLD), formerly referred to as non-alcoholic fatty liver disease (NAFLD), this association has been controversial.

Methods

A comprehensive literature search was undertaken up to February 1, 2022, in the PubMed, Embase, Web of Science, CNKI, WANFANG, and CBM library databases. Circulating chemerin levels were obtained and summarized using the standardized mean difference (SMD) and 95% confidence interval (CI). Subgroup and meta-regression analyses were conducted to examine the possibility of heterogeneity.

Results

A total of 17 studies involving 2580 participants (1584 MAFLD patients and 996 controls) evaluated circulating chemerin levels in patients with MAFLD. The present study showed that higher chemerin levels were found in patients with MAFLD (SMD: 1.32; 95% CI: 0.29, 2.35) and nonalcoholic fatty liver (NAFL) (SMD: 0.75; 95% CI: 0.01, 1.50) compared to controls. However, circulating chemerin levels did not differ significantly in the following comparisons: nonalcoholic steatohepatitis (NASH) patients and controls (SMD: 0.75; 95% CI: -0.52, 2.03); NASH patients and NAFL patients (SMD: 0.16; 95% CI: -0.39, 0.70); moderate to severe steatosis and mild steatosis (SMD: 0.55; 95% CI: -0.59, 1.69); present liver fibrosis and absent liver fibrosis (SMD: 0.66; 95% CI: -0.42, 1.74); present lobular inflammation and absent lobular inflammation (SMD: 0.45; 95% CI: -0.53, 1.42); and present portal inflammation and absent portal inflammation (SMD: 1.92; 95% CI: -0.85, 4.69).

Conclusions

Chemerin levels were considerably greater in patients with MAFLD than in controls, despite the fact that they were not significantly linked to different liver tissue lesions of MAFLD. In different subtypes of MAFLD, in comparison to healthy controls, the chemerin levels of NAFL patients were higher, whereas, there was no obvious difference in chemerin levels between NASH patients and controls. It is possible that chemerin will be used as a biomarker in the future to track the development and progression of MAFLD.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12944-022-01637-7.

Epidemiology and Clinical Outcomes of Metabolic (Dysfunction)-associated Fatty Liver Disease

Metabolic (dysfunction)-associated fatty liver disease (MAFLD) is currently the most common chronic liver disease and affects at least a quarter of the global adult population. It has rapidly become one of the leading causes of hepatocellular carcinoma and cirrhosis in Western countries. In this review, we discuss the nomenclature and definition of MAFLD as well as its prevalence and incidence in different geographical regions. Although cardiovascular disease remains the leading cause of death in MAFLD patients, the proportion of patients dying from hepatic complications increases sharply as the disease progresses to advanced liver fibrosis and cirrhosis. In addition, patients with MAFLD are at increased risk of various extrahepatic cancers. Although a causal relationship between MAFLD and extrahepatic cancers has not been established, clinicians should recognize the association and consider cancer screening (e.g., for colorectal cancer) as appropriate.

Reenvisioning Traditional to Regenerative Therapeutic Advances in Managing Nonalcoholic Fatty Liver Disease in Diabetes Mellitus

Reports indicate the increasing prevalence of liver disorders in diabetes mellitus (DM) patients. Clinically, it has also been revealed that the existence of nonalcoholic fatty liver disease (NAFLD) enhances the incidence of type 2 diabetes mellitus (T2DM), while T2DM exacerbates NAFLD to extremely severe forms of steatohepatitis, cirrhosis, and hepatocellular carcinoma. This implies the coexistence and bidirectional nature of NAFLD and T2DM, which function synergistically to drive adverse consequences in clinical practice. For treatment of such comorbid state, though the existing practices such as lifestyle management, traditional Chinese medicines (TCM), and pharmaceuticals have offered somewhat relief, the debate continues about the optimal therapeutic impacts. Recent developments in the field of tissue engineering have led to a renewed interest in novel biomaterial alternatives such as stem cells. This might be attributable to their differentiation potential towards hepatic and pancreatic lineage. These cellular therapies could be further complemented by platelet-derived biomaterials, TCM formulations, or any specific drug. Based on these abovementioned approaches, we aimed to comprehensively analyze various preclinical and clinical studies from traditional to regenerative therapeutic approaches in managing concomitant NAFLD and T2DM.

Impact of aging on primary liver cancer: epidemiology, pathogenesis and therapeutics

Aging involves progressive physiological and metabolic reprogramming to adapt to gradual deterioration of organs and functions. This includes mechanisms of defense against pre-malignant transformations. Thus, certain tumors are more prone to appear in elderly patients. This is the case of the two most frequent types of primary liver cancer, i.e., hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (iCCA). Accordingly, aging hallmarks, such as genomic instability, telomere attrition, epigenetic alterations, altered proteostasis, mitochondrial dysfunction, cellular senescence, exhaustion of stem cell niches, impaired intracellular communication, and deregulated nutrient sensing can play an important role in liver carcinogenesis in the elders. In addition, increased liver fragility determines a worse response to risk factors, which more frequently affect the aged population. This, together with the difficulty to carry out an early detection of HCC and iCCA, accounts for the late diagnosis of these tumors, which usually occurs in patients with approximately 60 and 70 years, respectively. Furthermore, there has been a considerable controversy on what treatment should be used in the management of HCC and iCCA in elderly patients. The consensus reached by numerous studies that have investigated the feasibility and safety of different curative and palliative therapeutic approaches in elders with liver tumors is that advanced age itself is not a contraindication for specific treatments, although the frequent presence of comorbidities in these individuals should be taken into consideration for their management.

The Troubling Link Between Non-alcoholic Fatty Liver Disease (NAFLD) and Extrahepatic Cancers (EHC)

Non-alcoholic fatty liver disease (NAFLD) is a fast-spreading epidemic across the globe and has serious implications far beyond that of a "benign" liver condition. It is usually an outcome of ectopic fat storage due to chronic positive energy balance leading to obesity and is associated with multiple health problems. While association with cardiovascular disease and hepatocellular cancer is well recognized, it is becoming clear the NAFLD carries with it an increased risk of cancers of extrahepatic tissues. Studies have reported a higher risk for cancers of the colon, breast, prostate, lung, and pancreas. Fatty liver is associated with increased mortality; there is an urgent need to understand that fatty liver is not always benign, and not always associated with obesity. It is, however, a reversible condition and early recognition and intervention can alter its natural history and associated complications.

Is there a link between non-alcoholic fatty liver disease aspects and pancreatic cancer? Results of a case-matched study

BACKGROUND AND AIMS

An association between non-alcoholic fatty liver disease (NAFLD) and pancreatic ductal adenocarcinoma (PDAC) has been previously suggested. This study aims at investigating this association and at identifying potential links between variables of the NAFLD spectrum and PDAC.

METHODS

A cross-sectional case-matched analytical and comparative study was carried out to analyze patients undergoing surgical resection of PDAC and compare them to a control group of individuals undergoing cholecystectomy at a public tertiary teaching hospital, matched by sex, age and BMI. Hepatic histopathological examinations were compared between cases and controls.

RESULTS

Of 56 individuals, 36 were male (64.3%) and the median age was 61.5 years old (interquartile range: 57.5 - 70). The participants' median BMI was 24.3 kg/m2 (interquartile range: 22.1-26.2 kg/m2). Microvesicular steatosis (p=0.04), hepatocellular ballooning (p=0.02), fibrosis (p=0.0003) and steatohepatitis (p=0.03) were significantly more frequent in the group of cases. Odds ratios for hepatocellular ballooning (6.2; 95%CI: 1.2-31.8; p=0.03), fibrosis (9.3; 95%CI: 2.5-34.1; p=0.0008) and steatohepatitis (3.9; 95%CI: 1.1-14.3; p=0.04) were statistically significant in relation to the PDAC prevalence.

CONCLUSIONS

Significant associations were identified between histopathological aspects of NAFLD (microvesicular steatosis, hepatocellular ballooning, fibrosis, and steatohepatitis) and PDAC.

Bariatric Surgery Reduces Cancer Risk in Adults With Nonalcoholic Fatty Liver Disease and Severe Obesity

BACKGROUND & AIMS

Nonalcoholic fatty liver disease (NAFLD) is associated with obesity and increased risk of cancer. The impacts of bariatric surgery on cancer risk in NAFLD patients are unknown. We investigated the effect of bariatric surgery on cancer risk in patients with NAFLD and severe obesity using the MarketScan database.

METHODS

We conducted a retrospective cohort study of 18 to 64 years old newly diagnosed NAFLD patients with severe obesity between 2007 and 2017. We used Cox proportional hazard models to examine the association between bariatric surgery, modeled as a time-varying covariate, and the risks of any cancer and obesity-related cancer, while accounting for confounding using inverse probability of treatment weighting (IPTW).

RESULTS

A total of 98,090 patients were included in the study, 33,435 (34.1%) received bariatric surgery. In those without surgery, 1898 incident cases of cancer occurred over 115,890.11 person-years of follow-up, compared with 925 cancer cases over 67,389.82 person-years among surgery patients (crude rate ratio, 0.84; 95% CI, 0.77- 0.91). The IPTW-adjusted risk of any cancer and obesity-related cancer was reduced by 18% (hazard ratio, 0.82; 95% CI, 0.76-0.89) and 25% (hazard ratio, 0.65; 95% CI, 0.56-0.75), respectively, in patients with versus without bariatric surgery. The adjusted risks of any cancer and obesity-related cancer were significantly lower in cirrhotic versus non-cirrhotic patients who underwent surgery. In cancer-specific models, bariatric surgery was associated with significant risk reductions for colorectal, pancreatic, endometrial, thyroid cancers, hepatocellular carcinoma, and multiple myeloma.

CONCLUSION

Bariatric surgery was associated with significant reductions in the risks of any cancer and obesity-related cancer in NAFLD patients with severe obesity.

Metformin: review of epidemiology and mechanisms of action in pancreatic cancer

Pancreatic ductal adenocarcinoma continues to be a lethal disease, for which efficient treatment options are very limited. Increasing efforts have been taken to understand how to prevent or intercept this disease at an early stage. There is convincing evidence from epidemiologic and preclinical studies that the antidiabetic drug metformin possesses beneficial effects in pancreatic cancer, including reducing the risk of developing the disease and improving survival in patients with early-stage disease. This review will summarize the current literature about the epidemiological data on metformin and pancreatic cancer as well as describe the preclinical evidence illustrating the anticancer effects of metformin in pancreatic cancer. Underlying mechanisms and targets of metformin will also be discussed. These include direct effects on transformed pancreatic epithelial cells and indirect, systemic effects on extra-pancreatic tissues.

Nonalcoholic fatty liver disease and risk of prostatic diseases: Roles of insulin resistance

Nonalcoholic fatty liver disease (NAFLD), the liver component of metabolic syndrome, is considered to be associated with high risk of prostatic diseases but a systematic review has not been conducted. Under a comprehensive review of the eligible clinical studies, a potential positive association between NAFLD and benign prostatic hyperplasia/prostate cancer (BPH/PCa) has been postulated. Insulin resistance and metabolic aberrations are considered to be the potential mechanism for such association. However, the relationship between NAFLD and other prostatic diseases, that is, prostatic inflammation and lower urinary tract symptoms, seems vague due to limited relevant studies in the literatures. The present review highlights that clinicians should be conscious of the detrimental effect of NAFLD on the development of BPH and PCa.

Evaluation and management of extrahepatic manifestations of nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is a multisystemic disease and a rapidly growing cause of chronic liver disease in children and adults worldwide. Diagnosis and management of extrahepatic manifestations of NAFLD, including cardiovascular disease (CVD), type 2 diabetes mellitus, metabolic syndrome, chronic kidney disease, obstructive sleep apnea, polycystic ovarian syndrome, hypothyroidism, psoriasis, and extrahepatic malignancy are crucial for the treatment of patients with NAFLD. The leading cause of death in NAFLD is primarily from CVD, followed by liver-related mortality, extrahepatic cancer, liver cancer, and diabetes-related mortality. Therefore, clinicians need to identify high-risk patients earlier in the disease course and be aware of the extrahepatic manifestations of NAFLD to improve liver disease outcomes. In this review, we focus on the monitoring and management of the extrahepatic manifestations of NAFLD.

Complications of Non-Alcoholic Fatty Liver Disease in Extrahepatic Organs

Non-alcoholic fatty liver disease (NAFLD) is now recognized as the most common chronic liver disease worldwide, along with the concurrent epidemics of metabolic syndrome and obesity. Patients with NAFLD have increased risks of end-stage liver disease, hepatocellular carcinoma, and liver-related mortality. However, the largest cause of death among patients with NAFLD is cardiovascular disease followed by extrahepatic malignancies, whereas liver-related mortality is only the third cause of death. Extrahepatic complications of NAFLD include chronic kidney disease, extrahepatic malignancies (such as colorectal cancer), psychological dysfunction, gastroesophageal reflux disease, obstructive sleep apnea syndrome, periodontitis, hypothyroidism, growth hormone deficiency, and polycystic ovarian syndrome. The objective of this narrative review was to summarize recent evidences about extrahepatic complications of NAFLD, with focus on the prevalent/incident risk of such diseases in patients with NAFLD. To date, an appropriate screening method for extrahepatic complications has not yet been determined. Collaborative care with respective experts seems to be necessary for patient management because extrahepatic complications can occur across multiple organs. Further studies are needed to reveal risk profiles at baseline and to determine an appropriate screening method for extrahepatic diseases.