Incidence, Mortality, and Survival Trends in Cancer of the Gallbladder and Extrahepatic Bile Ducts in Lithuania.

Background and Objectives: Gallbladder cancer is a rare type of cancer, with aggressive clinical behavior. Limited treatment options provide poor survival prognosis. We aimed to investigate the incidence, mortality trends, and survival of gallbladder and extrahepatic bile duct cancer in Lithuania between 1998 and 2017. Materials and Methods: The study was based on the Lithuanian Cancer Registry database. The study included all cases of cancer of the gallbladder and extrahepatic bile ducts reported to the Registry in the period 1998-2017. Age-specific and age-standardized incidence rates were calculated. In addition, 95% confidence intervals for APC (Annual Percent Change) were calculated. Changes were considered statistically significant if p was <0.05. Relative survival estimates were calculated using period analysis according to the Ederer II method. Results: Age-standardized rates for gallbladder cancer and extrahepatic bile duct cancer among females decreased from 3.91 to 1.93 cases per 100.000 individuals between 1998 and 2017, and from 2.32 to 1.59 cases per 100.000 individuals between 1998 and 2017 among males. The highest incidence rates were found in the 85+ group with 27.5/100,000 individuals in females and 26.8/100,000 individuals in males. The 1-year as well as 5-year relative survival rates of both genders were 34.29% (95% CI 32.12-36.48) and 16.29% (95% CI 14.40-18.27), respectively. Conclusions: Incidence and mortality from gallbladder and extrahepatic bile duct cancer decreased in both sexes in Lithuania. Incidence and mortality rates were higher in females than in males. Relative 1-year and 5-year survival rates showed a steady increase during the study period among males and females.