A case-control assessment of risk factors for gallbladder carcinoma.

Gallbladder carcinoma is an uncommon, but highly fatal disease. Its symptoms frequently mirror those of gallstone disease, and in most instances, diagnosis is an incidental finding at surgery. While risk factors have been suggested for this cancer, many may in reality simply be a consequence of the older age of the population. This study is one of the few to approach this question by using a case-control study design comparing gallbladder carcinoma patients with a gallstone population, coupled with multivariate analysis to determine age-independent risk factors. Univariate analyses showed gallbladder carcinoma patients to be older than gallstone patients and to have many age-associated diseases. Following multiple regression adjustment for age, this disease was associated with female gender and with a previous history of gallstone symptoms. Carcinoma patients were less likely to have cholesterol gallstones in their gallbladders at surgery. A previous history of smoking was a substantial risk but of borderline statistical significance. Previous studies report associations that may be due to the older age of the gallbladder carcinoma patient. Our results show that after adjusting for age with multivariate analysis, gallbladder cancer subjects were predominantly female, more likely to report previous gallstone symptomology, and to smoke. While gallstones were not universally isolated from carcinoma patients at cholecystectomy, when present, they were less frequently classified as cholesterol gallstones based on visual inspection. Further cohort studies which target these populations will allow us to gain a more solid consensus on the risk factors for this disease.