Epidemiology, survival and new treatment modalities for intrahepatic cholangiocarcinoma (IHCC).

e16217 Background: Intrahepatic cholangiocarcinoma (IHCC), a rare biliary tract cancer, has been rising in incidence and is associated with poor survival. With the advent of new treatment modalities and various ongoing research, population-based perspective can be helpful to reflect the progress in managing this deadly disease and provide updated outcome information as a reference for comparison during upcoming clinical studies. We would like to provide a 20-year update on incidence and survival with reference to landmark trials, with a focus on survival outcomes of the recent 5 years for future insights. Recent and ongoing clinical trials will be discussed. Methods: This study extracted population data from the Surveillance, Epidemiology, and End Results (SEER) database. Age-adjusted incidence rate (AAIRs) and survival rate (SR) trends were calculated from January 2000 to December 2020 using 22 registries for the US population. Incidence and survival rates were collected from the SEER database, reported per 100,000 population and age adjusted to the 2020 US standard population. The annual percent change (APC) was used to report long term trends. Results: In this analysis of 19,948 IHCC patients, the AAIR increased from 0.49 per 100,000 in 2000 to 1.38 in 2020 (APC 6.94, 95% CI 6.32 to 7.56), with a notable decline from 2019 to 2020. Incidence rates overall displayed an uptrend course across subgroups divided by sex, race, age, and disease stage. The age-adjusted mOS climbed from 5.28 months in 2000 to 9.3 months in 2013, maintaining between 8.0-9.0 months after 2013. Using 2010 as a cutoff, when the ABC-02 trial was published, the decade-based mOS increased from 6.55 in 2000-2010 to 9.06 in 2010-2020, which remained statistically significant at 1-year, 3-year, and 5-year OS. During 2015-2020, the overall mOS was 8.8 months, with mOS of 24.3 months, 12.1 months, and 5.4 months for local, regional, and distant stages, respectively. Conclusions: These results indicate a steady rise in IHCC incidence since 2000, consistent across all subgroups. Survival rates have improved since 2000 but stabilized after 2013, following the publication of the ABC-02 trial published in 2010, which used systemic gemcitabine and cisplatin for unresectable iHCC. Updated survival data from 2015 onwards will serve as a reference of comparison for forthcoming clinical trials.