Increased risk of colorectal malignant neoplasm in patients with nonalcoholic fatty liver disease: a large study

Nonalcoholic fatty liver disease (NAFLD) has been suggested to be a strong risk factor of colorectal benign adenomas and advanced neoplasms. The aim of this large cohort study was to further investigate the prevalence of colorectal malignant neoplasm (CRMN) in patients with NAFLD and determine whether association between NAFLD and CRMN exists. 2,315 community subjects (1,370 males and 945 females) who underwent a routine colonoscopy according to international colorectal cancer screening guideline were recruited. Nature of colorectal lesions determined by biopsy and NAFLD was diagnosed by ultrasound. Binary logistic regression analysis was applied to explore the related associations. Prevalence of CRMN was 29.3% (77/263) in patients with NAFLD, which was significantly higher than 18.0% (369/2,052) in the control group (P<0.05). In addition, malignant neoplasm in NAFLD group occurred more frequently at sigmoid colon than in control group (14.3 vs. 11.9%). The incidence of highly-differentiated colorectal adenocarcinoma in NAFLD group was significantly higher than control group (62.3 vs. 9.8%). Univariate analysis showed that NAFLD had strong association with CRMN (OR 2.043; 95% CI 1.512-2.761; P<0.05). After adjusting for metabolic and other confounding factors, NAFLD remained as an independent risk factor for CRMN (OR 1.868; 95% CI 1.360-2.567; P<0.05). NAFLD was an independent risk factor for CRMN. Sigmoid carcinoma and highly differentiated colorectal adenocarcinoma were more commonly found in NAFLD. (ClinicalTrials.gov number, NCT01657773, website: http://clinicaltrials.gov/ct2/show/NCT01657773?term=zheng+minghua&rank=1 ).