Temporal trends in incidence and mortality in biliary tract cancers in the United States, 2000–2023: A SEER-based analysis.

e16153 Background: Biliary tract cancers (BTCs) are aggressive malignancies with an increasing global burden. In the United States, recent changes in cholangiocarcinoma incidence and mortality, as well as demographic disparities, warrant clarification using contemporary national cancer data. Methods: We extracted incidence and mortality data from the SEER 21 registries (2000–2023). Biliary tract cancers were classified as intrahepatic cholangiocarcinoma (C22.1), extrahepatic cholangiocarcinoma (C24.0), or gallbladder cancer (C23.9). Histology was restricted to cholangiocarcinoma (8160/3) for bile duct sites, while all malignant histologies were included for gallbladder cancer. Age-adjusted rates were expressed per 100,000 person-years using the 2000 U.S. standard population. Temporal trends were evaluated by log-linear regression to estimate the Annual percent change (APC). Results: Intrahepatic cholangiocarcinoma increased by +5.14% annually (p<0.001), with a parallel rise in mortality by +3.32% (p<0.001). Extrahepatic cholangiocarcinoma showed smaller but still significant increases in incidence (+1.67%/year, p<0.001) and mortality (+1.30%/year, p<0.001). Conversely, gallbladder cancer incidence (−0.42%/year, p=0.20) and mortality (−0.39%/year, p=0.22) remained stable Table 1. Asian/Pacific Islanders exhibited the highest intrahepatic incidence rates, while Black individuals had disproportionately higher gallbladder mortality. Sex-specific analyses showed that males had higher cholangiocarcinoma incidence, whereas females had higher gallbladder cancer rates. Despite increased intrahepatic incidence, the mortality-to-incidence ratio remained high across all subtypes, demonstrating persistently poor outcomes. Conclusions: Intrahepatic and extrahepatic cholangiocarcinoma represent a rapidly growing cancer burden in the United States, while gallbladder cancer trends remain stable. Racial and sex disparities persist, underscoring a need for targeted prevention, earlier detection, and equitable access to care. These findings support BTC as an emerging public health priority. Incidence and mortality annual percent change with significance by cancer type. Category Anatomical Site Annual Percent Change (APC %) P-value Incidence Intrahepatic cholangiocarcinoma +5.14% <0.001 Extrahepatic cholangiocarcinoma +1.67% <0.001 Gallbladder cancer -0.42% 0.20 Mortality Intrahepatic cholangiocarcinoma +3.32% <0.001 Extrahepatic cholangiocarcinoma +1.3% <0.001 Gallbladder cancer -0.39% 0.22