S2918 Trends in Mortality From Malignant Neoplasms of Liver and Intrahepatic Bile Ducts in the United States: A Retrospective Analysis From 1999 to 2020

Introduction: Primary malignant neoplasms of the liver are the sixth most commonly diagnosed cancer and the third most common cause of cancer-related mortality. We analyzed the mortality trends of all types of primary liver cancers, including HCC, cholangiocarcinoma, and other rare types of primary malignant neoplasms of liver to help better assess the trends in overall burden of this group of cancers. Methods: CDC WONDER database was analyzed, and International Classification of Diseases, Tenth Revision (ICD-10) codes were utilized to identify deaths from primary malignant neoplasms of liver from 1999 to 2020 in patients aged 25 or greater. The age-adjusted mortality rates (AAMR/100,000) for the population were extracted, and trends were analyzed for age, gender, race, and year. Results: There were a total of 445,389 deaths from primary liver cancer from 1999 to 2020. AAMR increased from 6.95 in 1999 to 10.12 in 2020. Gender analysis showed that both sexes have shown a gradual increase in AAMR over the course of years. The mean AAMR for men was 13.09 per 100,000 population (range: 12.31–13.87; SD: 1.75), which was more than twice the rate observed in women (mean: 5.45; range: 5.16–5.74; SD: 0.66). Race analysis showed that Asian or Pacific Islanders are the only race, that has shown an overall decreasing trend in mortality from liver cancer, with AAMR decreasing from 15.68 in 1999 to 12.15 in 2020. Despite the decreasing trend, Asian or Pacific Islanders still have the highest mean AAMR (mean: 14.83; range: 14.21-15.46; SD: 1.41), followed by Hispanics (13.15), Black or African Americans (11.52), American Indian or Alaskan Native (10.51), and finally White (8.32). Conclusion: An important aspect of understanding the disparities in mortality from primary liver cancer will be to see these disparities in the context of HCC, which accounts for 85 percent of primary liver malignancies. The decreasing mortality trend from primary liver cancer observed in Asians is consistent with a decreasing trend in mortality from HCC due to a decreasing incidence of HBV. The increased mortality from primary liver cancer among men noted throughout the study period can be attributed to higher incidences of HBV and HCV infections, as well as greater alcohol consumption, all of which contribute to the development of HCC. With an increasing mortality trend from primary malignant neoplasms of the liver, further research is needed to mitigate the risk factors and advance the treatment modalities for liver cancer.