Abstract C36: Cancer incidence disparities among the Asian American population

Introduction: Asian Americans are the fastest growing race group in the United States, accounting for 5.7% of the total population in 2010. Previous research using cancer registry data studied cancer incidence rates by specific Asian group. However, those rates were underestimated, and possibly biased in relative terms, because Asian cancer cases without a recorded specific Asian group (also called not otherwise specified, NOS) were not taken into account. The purpose of this study was to produce comparable incidence rates for the six major Asian groups (Chinese, Filipino, Japanese, Korean, South Asian, and Vietnamese) by statistically adjusting for Asian NOS cases. Methods: Cancer incidence data between 2009 and 2011 were obtained from the eight states with the highest numbers of Asian Americans covering 68.3% of the total Asian American population, the largest coverage for a study on specific Asian groups to date. Population denominators were derived from 2010 US Census. Asian NOS cases were distributed using stratified imputation by age, cancer site, gender, and geographic region. Age-standardized incidence rates for 19 cancer sites were computed for specific Asian groups and non-Hispanic whites to detect potential disparities among the Asian American population. In addition, incidence rates were compared with those in their countries of origin to investigate the changes in cancer risk associated with immigration to the United States. Results: A total of 93,626 Asian and 1,325,051 non-Hispanic white cancer cases were analyzed. Asian Americans had significantly lower overall incidence rates than non-Hispanic whites (333.1 per 100,000 and 540.7 for men, and 299.4 and 448.5 for women, respectively). Filipino men (377.3) and Japanese women (343.0) had the highest overall incidence rates while South Asian men (296.8) and Korean women (276.2) had the lowest among specific Asian groups. Compared to their countries of origin, the overall incidence rates were higher in Asian Americans except among Koreans. Conclusions: Asian Americans are disproportionately burdened by infection-related cancers, such as liver and stomach cancers, but not by cervical cancer. Considerable incidence disparities exist among specific Asian groups. Compared to non-Hispanic whites and other Asian groups, significantly higher colorectal cancer rates were observed in Japanese, stomach cancer in Koreans, nasopharyngeal cancer in Chinese, thyroid cancer in Filipinos, and liver cancer in Vietnamese. The disparities here found demonstrate the need for future research to explore the factors behind the increased susceptibility for some cancers and the apparent “protection” against others evident among specific Asian groups. In addition, public health efforts are needed to eliminate cancer disparities among specific Asian groups through improved prevention, screening and surveillance. Citation Format: Hongbin Jin, Paulo S. Pinheiro. Cancer incidence disparities among the Asian American population. [abstract]. In: Proceedings of the Eighth AACR Conference on The Science of Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; Nov 13-16, 2015; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2016;25(3 Suppl):Abstract nr C36.