Characteristics of incident liver cancer cases in the District of Columbia metropolitan area.

The District of Columbia (D.C.) has the highest liver cancer incidence in the United States (U.S.), but the reasons for this are not fully known. We examined socio-demographic, clinical and behavioral characteristics of incident liver cancer cases in D.C., Maryland (MD) and Virginia (VA) to identify potential risk factors. We obtained data from D.C., MD and VA cancer registries for individuals diagnosed with hepatocellular carcinoma (HCC) or intrahepatic cholangiocarcinoma (ICC) between 2013 and 2016. We estimated age-adjusted incidence rates and conducted descriptive analyses stratified by state/territory, sex, stage at diagnosis, and race/ethnicity. 5,928 incident HCC/ICC cases occurred between 2013-2016. Age-adjusted incidence rates (per 100,000) for HCC/ICC were highest in D.C. (12.2, 95% CI=10.9, 13.5), for males (12.6, 95% CI=12.2, 12.9), and non-Hispanic Blacks (11.3, 95% CI=10.8, 11.8) and Asian/Pacific Islanders (APIs) (10.8, 95% CI=9.7, 11.9). Racial disparities in HCC/ICC incidence were widest in D.C. A substantial proportion of cases were missing data on country of birth and behavioral risk factors. Mean age at diagnosis, marital status, country of birth, insurance status, and alcohol and tobacco use history varied across analytic sub-groups. Non-Hispanic Blacks, APIs and males experience a high burden of liver cancer in the D.C. metropolitan area. There are several socio-demographic disparities by state/territory, sex, and race/ethnicity. More data on country of birth, behavioral risk factors, and comorbidities are urgently needed to understand their contribution to the burden of liver cancer in the D.C. metropolitan area.