Cancer Distribution Among Asian, Native Hawaiian, and Pacific Islander Subgroups — United States, 2015–2019

Summary

What is already known about this topic?

Non-Hispanic Asian and non-Hispanic Native Hawaiian and Pacific Islander (NHPI) persons represent a growing segment of the U.S. population, and are often aggregated in analyses.

What is added by this report?

Cancer incidence among 25 Asian and NHPI subgroups differed by sex, age, cancer type, and stage at diagnosis. For example, lung cancer was the most common cancer among Chamoru, Micronesian, and Vietnamese persons; colorectal cancer was the most common cancer among Cambodian, Hmong, Laotian, and Papua New Guinean persons.

What are the implications for public health practice?

Understanding cancer distribution among Asian and NHPI subgroups might help guide development and implementation of culturally and linguistically relevant programs addressing health disparities and social determinants of health.

Non-Hispanic Asian (Asian) and non-Hispanic Native Hawaiian and Pacific Islander (NHPI) persons represent growing segments of the U.S. population (1). Epidemiologic cancer studies often aggregate Asian and NHPI persons (2,3); however, because Asian and NHPI persons are culturally, geographically, and linguistically diverse (2,4), subgroup analyses might provide insights into the distribution of health outcomes. To examine the frequency and percentage of new cancer cases among 25 Asian and NHPI subgroups, CDC analyzed the most current 2015–2019 U.S. Cancer Statistics data.* The distribution of new cancer cases among Asian and NHPI subgroups differed by sex, age, cancer type, and stage at diagnosis (for screening-detected cancers). The percentage of cases diagnosed among females ranged from 47.1% to 68.2% and among persons aged <40 years, ranged from 3.1% to 20.2%. Among the 25 subgroups, the most common cancer type varied. For example, although breast cancer was the most common in 18 subgroups, lung cancer was the most common cancer among Chamoru, Micronesian race not otherwise specified (NOS), and Vietnamese persons; colorectal cancer was the most common cancer among Cambodian, Hmong, Laotian, and Papua New Guinean persons. The frequency of late-stage cancer diagnoses among all subgroups ranged from 25.7% to 40.3% (breast), 38.1% to 61.1% (cervical), 52.4% to 64.7% (colorectal), and 70.0% to 78.5% (lung). Subgroup data illustrate health disparities among Asian and NHPI persons, which might be reduced through the design and implementation of culturally and linguistically responsive cancer prevention and control programs, including programs that address social determinants of health.

Invasive cancer cases were defined according to the World Health Organization International Classification of Diseases for Oncology, Third Edition^† diagnosed during 2015–2019 using the most current U.S. Cancer Statistics data. This source of high-quality incidence data from population-based cancer registries, supported by CDC’s National Program of Cancer Registries and the National Cancer Institute’s Surveillance, Epidemiology, and End Results Program, covers approximately 99% of the U.S. population during the 5-year period.

Central cancer registries collect race and ethnicity information from different sources, including self-reported intake questionnaires, abstracted patient records, electronic health records, linkages to administrative databases, and algorithms to impute missing data (5). The current analysis is restricted to Asian and NHPI persons who reported non-Hispanic ethnicity. Race was recorded by standardized coding methods using 30 race groups, including 25 Asian and NHPI subgroups.^§ Some subgroups were defined by region rather than race (e.g., Micronesian race NOS). Because of low case counts, in some analyses, Cambodian, Hmong, Laotian, and Thai persons were aggregated into an Other Southeast Asian group.^¶ Data for other racial groups are available in the Data Visualizations Tool** (Supplementary Table, https://stacks.cdc.gov/view/cdc/126010). Cases were stratified by race, sex, and age for all cancers combined and then categorized into the 10 most common cancer types among all Asian and NHPI persons. A subset of cancer types detectable by screening^†† (i.e., female breast, colon and rectum, lung and bronchus, and cervix uteri) were further categorized by stage at diagnosis as early-stage, late-stage, or unknown.^§§ Because current national population denominators are not available for all subgroups, results are presented as frequencies and percentages rather than rates. In all analyses, cells containing fewer than six cases were suppressed to protect confidentiality and reduce misinterpretation or misuse of unstable counts. This activity was reviewed by CDC and was conducted consistent with applicable federal law and CDC policy.^¶¶

During 2015–2019, a total of 273,656 new invasive cancer cases were reported among Asian persons and 18,491 among NHPI persons in the United States (Table 1); these included 92,562 in East Asian persons (31.7% of all cases among Asian and NHPI persons), 71,721 in Southeast Asian persons (24.5%), 44,890 in South Asian persons (15.4%), and 64,483 in Other Asian persons (22.1%). Approximately one half of cases among Asian (56.2%) and NHPI (56.5%) persons were diagnosed in females, and approximately one tenth were diagnosed in persons aged <40 years (including 8.5% in Asian and 9.6% in NHPI persons). Across subgroups, the highest percentages of new cancer cases among females occurred among Tahitian (68.2%), Thai (65.5%), and Fiji Islander (65.1%) subgroups. The percentage of new cancer cases in persons aged <40 years was highest among Hmong (20.2%), Micronesian race NOS (18.1%), and Melanesian race NOS persons (15.7%), and lowest among Japanese persons (3.1%).

Breast cancer accounted for the highest proportion of new cancer diagnoses among 18 (72.0%) of the 25 Asian and NHPI subgroups. Lung cancer was the most common cancer among Chamoru, Micronesian race NOS, and Vietnamese persons; colorectal cancer was the most common cancer among Cambodian, Hmong, Laotian, and Papua New Guinean persons (Table 2) (Supplementary Table, https://stacks.cdc.gov/view/cdc/126010).

Among Asian and NHPI subgroups, the frequency of late-stage diagnoses for screening-detected cancers ranged from 25.7% (Japanese) to 40.2% (Other Southeast Asian) and 40.3% (Pacific Islander) for breast cancer; from 38.1% (Other Asian) to 61.1% (Korean) for cervical cancer; from 52.4% (Other Asian) to 64.7% (Other Southeast Asian) for colorectal cancer; and from 70.0% (Other Asian) to 78.5% (Other Southeast Asian) for lung cancer (Table 3).

Abbreviation: NOS = not otherwise specified.
* Early-stage (localized) cancer is confined to the primary site, and late-stage (regional or distant stage) cancer has spread to lymph nodes or other parts of the body. Cases identified only through autopsies or death certificates were excluded from the stage analyses.
^† Cancer incidence data were compiled from cancer registries that meet the data quality criteria for all invasive cancer sites combined, representing 99% of the U.S. population.
^§ The current analysis is restricted to persons who reported non-Hispanic ethnicity.
^¶ Groups were combined as follows: Other Southeast Asian includes Cambodian, Hmong, Laotian, and Thai persons; South Asian includes Asian Indian, Pakistani, and Asian Indian or Pakistani race NOS persons; Pacific Islander includes Chamoru, Fiji Islander, Guamanian race NOS, Melanesian race NOS, Micronesian race NOS, Papua New Guinean, Polynesian race NOS, Samoan, Tahitian, Tongan, and Pacific Islander race NOS persons; Other Asian includes data for persons whose race was not further specified or who are members of racial groups that did not include the other 24 Asian American, Native Hawaiian, or other Pacific Islander subgroups.
** Counts were suppressed because fewer than six cases were reported.