title: Association between fecal bile acids and colorectal cancer: a meta-analysis of observational studies.
abstract: OBJECTIVE
  To provide a systematic review with meta-analysis for addressing the relationship between fecal bile acids (FBAs) and colorectal cancer.
  
  
  METHODS
  Electronic databases were searched for all observational studies that examined the relationship between FBAs and colorectal cancer or adenoma, and calculated weighted mean difference (WMD) and 95% confidence interval (CI). Publication bias was assessed with funnel plot.
  
  
  RESULTS
  Twenty case-control or cohort studies were identified. All studies were pooled to assess the relationship between total FBAs and cancer/adenoma of the large bowel, however, no association was seen (WMD 0.61mg/g freeze-dried feces; 95% CI: -0.35-1.57). Significantly increased concentration of chenodeoxycholic acid (CDCA) was seen while pooling to assess the relationship between CDCA and cancer/adenoma of the large bowel (WMD 0.13 mg/g freeze-dried feces; 95% CI: 0.01-0.25), especially for colorectal cancer (WMD 0.28mg/g freeze-dried feces; 95% CI: 0.10-0.46). However, no significant differences in deoxycholic acid (DCA), lithocholic acid (LCA), and primary and secondary bile acids, were seen between patients with cancer and patients with matched controls regardless of fixed and random effects models.
  
  
  CONCLUSIONS
  CDCA might play a role in the etiology of colorectal cancer.
authors.affiliation: Department of Gastroenterology, Ren Ji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Institute of Digestive Disease, Shanghai, China.
authors.forename: Jin Lu
authors.initials: JL
authors.lastname: Tong
authors.forename: Zhi Hua
authors.initials: ZH
authors.lastname: Ran
authors.forename: Jun
authors.initials: J
authors.lastname: Shen
authors.forename: Guo Quan
authors.initials: GQ
authors.lastname: Fan
authors.forename: Shu Dong
authors.initials: SD
authors.lastname: Xiao
mesh_terms: D001647:Bile Acids and Salts / Q000378:metabolism*; D002277:Carcinoma / Q000209:etiology / Q000378:metabolism*; D016022:Case-Control Studies; D015331:Cohort Studies; D015179:Colorectal Neoplasms / Q000209:etiology / Q000378:metabolism*; D005243:Feces / Q000737:chemistry*; D005260:Female; D006801:Humans; D008297:Male
chemical_list: D001647:Bile Acids and Salts