Association of nonalcoholic fatty liver disease and liver cancer

AIM:To investigate the association between nonalcoholic fatty liver disease(NAFLD) and liver cancer,and NAFLD prevalence in different liver tumors.METHODS:This is a retrospective study of the clinical,laboratory and histological data of 120 patients diagnosed with primary or secondary hepatic neoplasms and treated at a tertiary center where they underwent hepatic resection and/or liver transplantation,with subsequent evaluation of the explant or liver biopsy.The following criteria were used to exclude patients from the study:a history of alcohol abuse,hepatitis B or C infection,no tumor detected in the liver tissue examined by histological analysis,and the presence of chronic autoimmune hepatitis,hemochromatosis,Wilson's disease,or hepatoblastoma.The occurrence of NAFLD and the association with its known risk factors were studied.The risk factors considered were diabetes mellitus,impaired glucose tolerance,impaired fasting glucose,body mass index,dyslipidemia,and arterial hypertension.Presence of reticulin fibers in the hepatic neoplasms was assessed by histological analysis using slide-mounted specimens stained with either hematoxylin and eosin or Masson's trichrome and silver impregnation.Analysis of tumor-free liver parenchyma was carried out to determine the association between NAFLD and its histological grade.RESULTS:No difference was found in the association of NAFLD with the general population(34.2% and 30.0% respectively,95%CI:25.8-43.4).Evaluation by cancer type showed that NAFLD was more prevalent in patients with liver metastasis of colorectal cancer than in patients with hepatocellular carcinoma and intrahepatic cholangiocarcinoma(OR = 3.99,95%CI:1.78-8.94,P < 0.001 vs OR = 0.60,95%CI:0.18-2.01,P = 0.406 and OR = 0.70,95%CI:0.18-2.80,P = 0.613,respectively).There was a higher prevalence of liver fibrosis in patients with hepatocellular carcinoma(OR = 3.50,95%CI:1.06-11.57,P = 0.032).Evaluation of the relationship between the presence of NAFLD,nonalcoholic steatohepatitis,and liver fibrosis,and their risk factors,showed no significant statistical association for any of the tumors studied.CONCLUSION:NAFLD is more common in patients with liver metastases caused by colorectal cancer.

Risk factors associated with inflammatory bowel disease: A multicenter case-control study in Brazil

BACKGROUND The etiology of inflammatory bowel disease(IBD)is unknown,but it is believed to be multifactorial.The hygiene hypothesis proposes that better hygiene conditions would lead to less infectious disease during childhood and favor the development of immune-mediated diseases.AIM To test the hygiene hypothesis in IBD by assessing the environmental risk factors associated with IBD development in different regions of Brazil with diverse socioeconomic development indices.METHODS A multicenter case-control study was carried out with 548 Crohn’s disease(CD)and 492 ulcerative colitis(UC)outpatients and 416 healthy controls,from six IBD centers within different Brazilian states at diverse socioeconomic development stages.A semi-structured questionnaire with 87 socioeconomic and environmental questions was applied.Logistic regression model was created to assess the odds ratio(OR)with P value and 95%confidence intervals(CI).RESULTS Predictive variables for both diseases(CD and UC)were women[odd ratios(OR)=1.31;OR=1.69],low monthly family income(OR=1.78;OR=1.57),lower number of cohabitants(OR=1.70;OR=1.60),absence of vaccination(OR=3.11;OR=2.51),previous history of bowel infections(OR=1.78;OR=1.49),and family history of IBD(OR=5.26;OR=3.33).Associated risk factors for CD were age(18-39 years)(OR=1.73),higher educational level(OR=2.22),absence of infectious childhood diseases(OR=1.99).The UC predictive variables were living in an urban area(OR=1.62),inadequate living conditions(OR=1.48)and former smokers(OR=3.36).Appendectomy was a risk factor for CD(OR=1.58)with inverse association with UC(OR=4.79).Consumption of treated and untreated water was associated with risk of CD(OR=1.38)and UC(OR=1.53),respectively.CONCLUSION This is the first examining environmental exposures as risk factors for inflammatory bowel disease in Brazil.Most of the variables associated with disease risk support the role of the hygiene hypothesis in IBD development.