Abstract IA17: Observations and implications from examining cancer incidence rates and trends of ethnic Asian Americans

Abstract

Abstract Asian Americans are a fast-growing population group in the United States (US). The substantial heterogeneity within them (e.g., by origin, language, culture, immigration history, socioeconomic status, degree of acculturation, etc.) and its impact on health and cancer disparities are increasingly being recognized. Except for Japanese Americans, the majority of the ethnic Asian Americans are foreign-born. Monitoring cancer incidence rates and trends among immigrant populations, especially in comparison with those of their countries of origin and US, can provide valuable information for understanding cancer etiology and identifying modifiable environmental and behavioral risk factors. As population mobility increases globally with time, this area of research will become more important and needed. The Los Angeles Cancer Surveillance Program (LACSP) is the population-based cancer registry for Los Angeles County (LAC) in California with over 10 million residents. It is a member of the California Cancer Registry (CCR) and the National Cancer Institute’s Surveillance, Epidemiology, and End Results (SEER) Program. It is also the only U.S. cancer registry that has consistently reported cancer incidence for four ethnic Asian American populations (i.e., Chinese, Filipinos, Japanese, and Koreans) in its catchment area, which allows the comparisons of these largely immigrant populations against those of their countries of origin and US whites. The standardized and detailed data from LACSP and around the world published in the Cancer in Five Continents (CI5) volumes have enabled numerous international comparison studies. We used the CI5 online analysis tool, CI5plus, and extracted age-adjusted incidence rates by sex and cancer site in LAC for Chinese, Filipinos, Japanese, and Koreans, respectively, to compare with rates from China, Philippines, Japan, and South Korea, as well as those for whites from the SEER registries for the period of 1973-2012. We observed: 1) Cancer-specific incidence rates among all four Asian ethnic groups in LAC have deviated from the rates in their countries of origin to approaching US whites; 2) although their risks for some cancers decreased (e.g., cervical, gastric, and liver), their risks for other cancers increased (e.g., breast, uterine, non-Hodgkin lymphoma, and testicular); and 3) Filipino Americans display rather different cancer risk profiles from other ethnic Asian Americans. Our findings highlight the important changes in cancer-specific incidence rates and trends among the ethnic Asian American subgroups as compared to those of their countries of origin. These changes underline the significance of nongenetic factors, including environmental, behavioral, and lifestyle factors, in cancer development and deserve further attention. Along with existing literature on known differences in cancer risk among these subpopulations, our work will help establish priorities to decrease cancer burden among Asian immigrants. Citation Format: Lihua Liu, Juanjuan Zhang, Andrea Sipin-Baliwas, Amie Hwang, Mariana C. Stern, Myles Cockburn, Dennis Deapen. Observations and implications from examining cancer incidence rates and trends of ethnic Asian Americans [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 IA17.