Cancer mortality in Germany-born Americans and Germans

Introduction: Comparing cancer mortality and associated risk factors among immigrant populations in a host country to those in their country of origin reveals disparities in cancer risk, access to care, diagnosis, and disease management. This study compares cancer mortality between the German resident population and Germany-born individuals who migrated to the US. Methods: Cancer mortality data from 2008-2018 were derived for Germans from the World Health Organization database and for Germany-born Americans resident in four states (California, Florida, Massachusetts, and New York) from respective Departments of Vital Statistics. We calculated age-standardized mortality rates (ASMRs) using the European standard population and standardized mortality ratios (SMR) compared to the German resident population along with 95% confidence intervals (CIs). Results: Germany-born American males had lower ASMRs (253.8 per 100,000) than German resident population (325.6 per 100,000). The difference in females was modest, with ASMRs of 200.7 and 203.7 per 100,000, respectively. For all cancers, Germany-born American males had an SMR of 0.72 (95% CI: 0.70-0.74) and females 0.98 (95% CI: 0.95-1.00). Male SMRs among Germany-born Americans were significantly below one for oral cavity, stomach, colorectal, liver, lung, prostate, and kidney cancer. Among females, SMRs were below one for oral cavity, stomach, colorectal, gallbladder, breast, cervix uteri, and kidney cancer. For both sexes, SMRs were over one for bladder cancer (1.14 for males, 1.21 for females). Mortality was higher for lung cancer (SMR: 1.68), non-Hodgkin's lymphoma (1.18) and uterine cancer (1.22) among Germany-born American females compared to the German resident population. Conclusion: Germany-born American males but not females showed lower cancer mortality than German resident population. Disparities may stem from variations in risk factors (e.g., smoking and alcohol use) as well as differences in screening practices and participation, cancer treatment, besides some residual potential "healthy immigrant effect".