Background: Although overall cancer incidence and mortality have been declining in the United States (US) in recent years, liver cancer incidence and mortality have tripled since 1980. In 2019, an estimated 42,000 new cases of liver cancer will be diagnosed and there will be nearly 32,000 deaths from liver cancer. Hepatocellular carcinoma (HCC) is the most common form of primary liver cancer, and it generally progresses from chronic liver disease, such as cirrhosis. HCC and its etiologies are not evenly distributed in the population, with racial/ethnic minorities bearing a disproportionate burden of disease. Asians and Latinos currently have the highest incidence rates of HCC in the US. To investigate these disparities, we identified a sample of HCC patients at a large academic health system to compare their sociodemographic characteristics and clinical and behavioral risk factors by race/ethnicity. Methods: We used electronic health record (EHR) data to identify a cohort of primary care patients who had at least two outpatient visits to a UCLA primary care provider, at least one year apart, from 2006 to 2018, and who were between the ages of 18-75 years at the time of the visits (n = 280,619). Initial descriptive analyses were conducted to profile HCC cases by key demographics, including age, sex, and race/ethnicity, as well as by co-diagnoses, which may represent key contributing causes to the development of HCC. Results: In the primary care cohort, a total of 749 patients (0.002%) had a diagnosis of HCC. Prevalence of HCC was highest among Asians (0.6%), followed by African Americans (0.4%), Latinos (0.4%), and was lowest among Whites (0.2%). Among patients classified as other or unknown race the HCC prevalence was 0.15%, and 0.04%, respectively. The most common co-diagnoses among the HCC cases were: cirrhosis (58.9%), hepatitis C (HCV; 45.9%), hepatitis B (HBV; 26.3%), non-alcoholic fatty liver disease (NAFLD; 24.0%), non-alcoholic steatohepatitis (NASH; 23.0%), and alcoholic hepatitis (19.1%). Cirrhosis was the most common co-diagnosis for all racial/ethnic groups (Blacks=66.1%, Latinos=82.2%, Whites=54.8%), except Asians (49.1%). HBV was the most common co-diagnosis among Asians (62.9%), while HCV was the second most common co-diagnosis among Blacks (64.5%), Latinos (54.2%), and Whites (44.1%). Latinos were the most likely to have a co-diagnosis of alcoholic hepatitis (37.3%). Conclusion: We observed distinct patterns of co-diagnoses with precursor conditions by race/ethnicity in this sample of HCC cases. Although the cross-sectional nature of these analyses preclude attributing cause to co-diagnoses, these results are consistent with existing epidemiological data. Future longitudinal analyses will examine the timeline between diagnosis with HCC and the respective etiologies, and investigate factors that may facilitate or impede disease progression, which can inform future interventions to reduce racial/ethnic disparities in liver cancer.

Citation Format: Yvonne N Flores, Beth A Glenn, Folasade May, Lina Tieu, Carrie R Wong, Lucia Chen, Francisco Durazo, Roshan Bastani. Developing precision medicine approaches to address liver cancer disparities [abstract]. In: Proceedings of the Twelfth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2019 Sep 20-23; San Francisco, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(6 Suppl_2):Abstract nr D108.