Cholelithiasis in gallbladder cancer: coincidence, cofactor, or cause!

BACKGROUND: While gallstones are associated with cancers of the gallbladder, the actual nature of their relationship needs to be clarified. This would aid the recommendations on the need for prophylactic cholecystectomy. METHODS: A systematic search of the scientific literature was carried out using the Medline, the Embase, and the Cochrane Central Register of Controlled Trials for the years 1891-2009 to obtain access to all publications involving gallstones in gallbladder cancer. RESULTS: While some epidemiological evidence supports a causal relationship for gallstones in gallbladder cancer, other studies have demonstrated a relatively low incidence of gallbladder cancer in countries reporting a high incidence of gallstones as a whole. In those studies where gallstones appear to have a causative role for cancer, the risk increases with increasing size, volume and weight, and number of the stones. The impact of duration of the stone or its composition is not clear. Experimental evidence from studies examining the impact of artificially introducing gallstones in the gallbladder has failed to lead to carcinogenesis. CONCLUSIONS: The evidence at the current time indicates that gallstones are a cofactor in the causation of gallbladder cancer. Absolute proof of their role as a cause for gallbladder cancer is lacking. The recommendation for prophylactic cholecystectomy in countries reporting a high incidence of gallbladder cancer and associated gallstones needs to be tailored to the epidemiological profile of the place.