Global variations in gallbladder cancer incidence: What do recorded data and national estimates tell us?

On a global scale, gallbladder cancer is a relatively rare cancer with a striking variability in incidence across countries and world regions. We examined recent geographic variations worldwide based on national gallbladder cancer incidence estimates for the year 2022 from the GLOBOCAN database for 185 countries alongside recorded incidence data from the most recent volume of Cancer Incidence in Five Continents. In 2022, 122,491 new gallbladder cancer cases and 89,055 deaths were estimated to occur worldwide, of which 64.5% and 64.7% respectively were among females. The highest reported rates (ASR per 100,000) were in subpopulations of Northeastern regions of India and Southern Chile in both males (ASR of 6.1 and 5.3, respectively) and in females, though rates were two times higher than males (ASR of 14.9 and 15.4). The lowest incidence rates were reported in subpopulations of Uganda for males and South Africa for females (0.21 and 0.14, respectively). Recorded gallbladder cancer incidence rates among subnational populations within countries differed considerably from their respective national estimates and revealed a 100-fold variation in gallbladder cancer, highlighting the importance of subnational population-based cancer registry data in pinpointing areas of high risk, driving research and prioritizing tailored public health actions.