The epidemiology of gallbladder cancer: lifestyle related risk factors and limited surgical possibilities for prevention.

Cancer of the gallbladder is a rare cancer with a poor prognosis. Most patients die within 1 year. The incidence shows large geographic variation and is higher in females and in certain ethnic groups. Gallstones are closely related to this type of cancer. Studying risk factors such as lifestyle is hampered by the generally small size of the case-series. Nevertheless, the studies conducted so far provide some indication that cigarette smoking, alcohol consumption, obesity and specific dietary habits might affect the risk. In women, reproductive history seems to affect the risk as well. Incidence may be lowered by identifying high risk groups and offering preventive measures. Although gallstones are associated with higher risk, most people with untreated gallstones are at low risk of developing the cancer. Moreover, the cancer occurs at such an old age that prophylactic removal of a stone-containing gallbladder is not an appropriate measure for the prevention of gallbladder cancer. Probably at a higher risk are those who are exposed to stones for longer periods. An indicator of duration of exposure is not presently available; whether stone size can be such an indicator in specific conditions and populations needs to be studied further.