Abstract B112: Racial/ethnic differences in hepatocellular carcinoma (HCC) characteristics and outcomes: The Multiethnic Cohort
Authors: Barzi Afsaneh , Wang Songren , Setiawan Veronica Wendy 
Published: September 2020

Abstract
Backgrounds: Striking differences in HCC incidence rates have been observed in the Multiethnic Cohort, with Latinos having the highest rate, followed by Native Hawaiians, Japanese Americans, African Americans and whites. Here, we characterized differences in HCC underlying etiology, tumor characteristics and survival across these racial/ethnic groups. Methods: Incident HCC cases after cohort entry were identified via linkages to California and Hawaii SEER registries. For this analysis, we included cases linked to the fee-for-service Medicare between 1999-2014. Tumor characteristics and treatment data were obtained from SEER and underlying etiology was determined using Medicare claims data. Date and cause of death were ascertained using state death certificate files and the National Death Index. Cox models were used to calculate multivariable hazard ratio (HR) and 95% confidence intervals (CI) for overall death. Results: 359 incident cases of HCC (142 Japanese Americans, 106 Latinos, 46 whites, 42 African Americans, and 23 Native Hawaiians) were included in this analysis. The average age at HCC diagnosis was 75.1 years. The most common etiology was hepatitis C infection (HCV) (34.5%), followed by nonalcoholic fatty liver disease (NAFLD) (29.8%), and alcoholic liver disease (12.8%). There were significant ethnic differences in the underlying HCC etiology (P&lt;0.0001). African Americans (59.5%) and Latinos (40.6%) were more likely to be diagnosed with HCV-related HCC; NAFLD came second in these populations (16.7% in African Americans and 29.3% in Latinos). In Japanese Americans (31.7%) and Native Hawaiians (39.1%), NAFLD is the most common etiology followed by HCV (26.1% in Japanese Americans and 13.0% in Native Hawaiians). The proportions of HCV (34.8%) and NAFLD (32.6%) HCC were similar in whites. While the stage distribution was similar across ethnic groups (P=0.76), receipt of treatment varied significantly (P=0.0005). African Americans had the highest proportion of no treatment (50.0%), followed by Latinos (45.3%), Native Hawaiians (26.1%), Japanese Americans (26.1%), and whites (15.2%). HCC-related death (72.2%) was the most common cause of mortality. Median survival in whites was 14.7 months, Japanese Americans 12.4 months, Native Hawaiians 12.2 months, Latinos 8.8 months and African Americans 6.4 months. After adjusting for sex, cancer stage, underlying etiology and receipt of treatment, African Americans (HR=1.78; 95% CI: 1.04-3.06) had significantly higher mortality, while Latinos (HR=1.36; 95% CI: 0.87-2.12), Japanese Americans (HR=0.96; 95% CI: 0.63-1.46) and Native Hawaiians (HR=0.55; 95% CI: 0.29-1.05) had no significant differences in mortality compared to whites. Conclusions: We found significant ethnic differences in HCC underlying etiology, receipt of treatment and disease outcome. Acknowledging differences in underlying HCC etiology and access to treatment in different ethnic groups is important for improving HCC outcomes and reducing disparities.
Citation Format: Afsaneh Barzi, Songren Wang, Veronica Wendy Setiawan. Racial/ethnic differences in hepatocellular carcinoma (HCC) characteristics and outcomes: The Multiethnic Cohort [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 B112.