Liver cancer: A leading cause of cancer death in the United States and the role of the 1945–1965 birth cohort by ethnicity

Liver cancer is highly fatal and the most rapidly increasing cancer in the US, where chronic hepatitis C (HCV) infection is the leading etiology. HCV is particularly prevalent among the 1945-1965 birth cohort, the so-called “baby boomers”. Focusing on this cohort-etiology link, we aim to characterize liver cancer patterns for 15 unique US populations: White, African American, Mexican Immigrant, Mexican American, Cuban and Chinese, among others. METHODS: Individual-level mortality data from 2012–2016 from the health departments of 3 large states – California, Florida, New York – were pooled to compute liver cancer mortality rates for each racial/ethnic group and for 2 birth cohorts of interest: “1945–1965 cohort” and “older cohort”. RESULTS: Liver cancer is a major cause of cancer death among all US male groups and the leading cause in Mexican American men. Over 50% of the age-adjusted liver cancer mortality of White, African American, Mexican American, and Puerto Rican males came from the 1945-1965 birth cohort. In contrast, foreign-born male and all female populations had higher liver cancer mortality originating from the older cohort. Internationally, US White male baby boomers had a 49% higher liver cancer mortality rate than their counterparts in Europe (mortality rate ratio 1.49; 95% CI 1.43–1.56). CONCLUSIONS: Populations burdened disproportionately by liver cancer in the 1945–1965 cohort include US-born males who were all present in the US during the 1960s–1990s when significant HCV transmission took place; these individuals will benefit most from HCV screening and treatment. For the others, including all women, Asian subgroups, and especially burgeoning Hispanic immigrant populations, comprehensive liver cancer prevention efforts will require detailed study of the distribution of etiologies. LAY SUMMARY: Liver cancer, a major cause of cancer death among US males, is increasing. The causes of liver cancer are varied, including hepatitis C, hepatitis B, alcohol-related liver disease, and non-alcoholic fatty liver disease. Racial/ethnic groups are impacted differently, but the highest rates are seen among US-born men born between 1945–1965, the so-called “baby boomers”, whether White, Black, or Hispanic, likely linked to the known high prevalence of hepatitis C infection among this cohort.