title: Risk of colorectal cancer in chronic liver diseases: a systematic review and meta-analysis.
abstract: OBJECTIVE
  The risk of colorectal cancer (CRC) in various chronic liver diseases compared with the general population remains unclear. We performed a systematic review and meta-analysis to assess the risk of CRC in patients with chronic liver diseases before and after liver transplantation.
  
  
  METHODS
  Electronic databases were searched for studies assessing the risk of CRC in patients with chronic liver diseases. The primary outcome was the pooled risk of CRC among studies that reported the risk as standardized incidence rate (SIR).
  
  
  RESULTS
  Fifty studies that included 55,991 patients were identified. Among studies that included hepatitis and cirrhotic patients, the pooled SIR was 2.06 (P < .0001; 95% confidence interval (CI), 1.46-2.90) with moderate heterogeneity (I2= 49.2%), which appeared to be because of the difference between subgroup of diseases and the power of studies. Three studies reported an increased risk of CRC in primary sclerosing cholangitis patients (pooled SIR 6.70; P < .0001; 95% CI, 3.48-12.91) with moderate heterogeneity (I2= 36.3%), which appeared to be because of the difference between the power of studies. Among studies that included post-transplant patients, the pooled SIR was 2.16 (P < .0001; 95% CI, 1.59-2.94) with moderate heterogeneity (I2= 56.4%). Meta-regression showed a correlation between the proportion of autoimmune-related liver diseases and the risk of CRC.
  
  
  CONCLUSIONS
  Patients with chronic liver diseases had an increased risk of CRC compared with the general population, which persisted after liver transplantation. A more intensive surveillance for CRC is warranted in this population.
authors.affiliation: Section of Gastroenterology, Hepatology and Nutrition, Department of Medicine, The University of Chicago Medicine, Chicago, Illinois, USA.
authors.forename: Yuga
authors.initials: Y
authors.lastname: Komaki
authors.affiliation: Section of Gastroenterology, Hepatology and Nutrition, Department of Medicine, The University of Chicago Medicine, Chicago, Illinois, USA.
authors.forename: Fukiko
authors.initials: F
authors.lastname: Komaki
authors.affiliation: Division of Gastroenterology and Hepatology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA.
authors.forename: Dejan
authors.initials: D
authors.lastname: Micic
authors.affiliation: Digestive and Lifestyle Diseases, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan.
authors.forename: Akio
authors.initials: A
authors.lastname: Ido
authors.affiliation: Section of Gastroenterology, Hepatology and Nutrition, Department of Medicine, The University of Chicago Medicine, Chicago, Illinois, USA.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Sakuraba
mesh_terms: D001327:Autoimmune Diseases / Q000453:epidemiology; D015209:Cholangitis, Sclerosing / Q000453:epidemiology*; D002908:Chronic Disease; D015179:Colorectal Neoplasms / Q000453:epidemiology*; D006521:Hepatitis, Chronic / Q000453:epidemiology / Q000601:surgery; D006801:Humans; D015994:Incidence; D008103:Liver Cirrhosis / Q000453:epidemiology; D008107:Liver Diseases / Q000453:epidemiology* / Q000601:surgery; D016031:Liver Transplantation / Q000706:statistics & numerical data*; D018570:Risk Assessment