Dr Wolfgang Ahrens and colleagues identified risk factors of carcinoma of the extrahepatic biliary tract in men.
The team interviewed newly diagnosed and histologically confirmed patients aged 35 to 70 years old between 1995 and 1997 in Denmark, Sweden, France, Germany and Italy.
Population controls were frequency-matched by age and region.
Adjusted odds ratios and 95% confidence intervals were estimated by logistic regression.
|There was excess risk with a body mass index over 30 at age 35 years |
|European Journal of Gastroenterology and Hepatology|
The team assessed 153 patients and 1421 controls.
The participation proportion was 71% for patients and 61% for controls.
The team found that gallstone disease was corroborated as a risk factor for extrahepatic biliary tract carcinoma in men.
An excess risk was observed particularly for gall bladder tumors, and for a body mass index over 30 at age 35 years.
This association was even stronger if the body mass index was over 30 for the lowest weight in adulthood.
The research team found no clear association with infection of the gall bladder, chronic inflammatory bowel disease, hepatitis or smoking.
Some increase in risk was suggested for consumption of 40 to 80 g alcohol per day and more.
Dr Ahrens' team concluded, "Our study corroborates gallstones as a risk indicator in extrahepatic biliary tract carcinoma."
"Permanent overweight and obesity in adult life was identified as a strong risk factor for extrahepatic biliary tract carcinoma, whereas we did not find any strong lifestyle-associated risk factors."
"Inconsistent results across studies concerning the association of extrahepatic biliary tract carcinoma with overweight and obesity may be explained by the different approaches to assess this variable."