Incidence of Screening-Detectable Cancers Among Non-Hispanic American Indian and Alaska Native Populations 2014–2018 (Purchased/Referred Care Delivery Areas)

U.S. Cancer Statistics Data Briefs, No. 24
November 2021

This data brief uses the most recent data available at the time of publication. More recent data may be available in a newer data brief or in the U.S. Cancer Statistics Data Visualizations tool.

Screening-detectable cancers, specifically colorectal, lung, female breast, and cervical cancers, make up a large percentage of cancers among non-Hispanic American Indian/Alaska Native (AI/AN) populations. Incidence rates for these cancers vary by geographic region. The highest incidence rates were seen in the Southern Plains; lung cancer in males and breast cancer in females.  The lowest rates in males were observed for lung cancers in the Southwest and for cervical cancer in females in the East.

Purchased/Referred Care Delivery Areas (PRCDA) are counties that contain federally recognized tribal lands or are adjacent to tribal lands. Race classification for the non-Hispanic American Indian/Alaska Native (AI/AN) population is more accurate in these counties. Please see CDC’s Data Visualizations tool technical notes for more details.

Differences in the occurrence of certain types of cancer among AI/AN populations compared to other populations have been described previously.1 These differences could be due to a variety of factors, including different exposures to pollution,2 social factors, built environment,3, 4 and access to health services to find cancers early (screening).5

Screening-detectable cancers are cancers for which the U.S. Preventive Services Task Force has found evidence that early detection through the use of screening tests, together with follow-up of abnormal tests and treatment, is beneficial in reducing cancer-related deaths.6 Studying the distribution of these cancers may lend insight into reducing cancer risk and promoting cancer screening among AI/AN populations. This data brief analyzes screening-detectable cancer rates among AI/AN populations in PRCDA counties across six regions: Alaska, Northern Plains, Southern Plains, Pacific Coast, East, and Southwest.

Number of New Screening-Detectable Cancers 2014–2018

Figure 1. Percent Distribution of Screening-Detectablea Cancers Among All Cancers in AI/ANb Population by Sex, 2014–2018

aScreening-detectable cancers refer to cancers for which there are specific population-based screening recommendations with a net benefit in terms of reducing cancer deaths.
bAI/AN refers to non-Hispanic American Indian or Alaska Native individuals living in PRCDA counties.

Between 2014 and 2018, a total of 32,942 cancers were reported for the AI/AN population, with 15,605 for males and 17,337 for females.

Screening-detectable cancers accounted for 39% of all new cancers in AI/AN males and females during this period.

  • For AI/AN males, about a quarter (25%) of all new cancers were screening-detectable, of which lung cancer (14%) was the most common.
  • For AI/AN females, more than half (51%) of all new cancers were screening-detectable, of which breast (26%) and lung (13%) cancers were the most common.

Rates by Sex and Region

Figure 2. Age-adjusted Incidence Ratesa per 100,000 for Screening-Detectable Cancersb Among AI/ANc Populations by Sex and Region, 2014–2018

aRates are age-adjusted to the 2000 standard U.S. population.
bAnalysis was limited to cases that met the following age cutoffs: colorectal cancer, 45 or older; lung cancer, 50 or older; female breast cancer, 50 or older; cervical cancer, 20 or older. Single-year age data are not available in the dataset; therefore, the age cutoff for cervical cancer does not reflect the screening recommendation of 21 years.
cAI/AN refers to non-Hispanic American Indian or Alaska Native individuals living in PRCDA counties.

  • Sex-specific rates of each screening-detectable cancer in Alaska, the Northern Plains, and the Southern Plains were higher than their corresponding rates in the overall US AI/AN population. Meanwhile, rates in the East and Southwest were lower than the corresponding rates in the overall US AI/AN population.
  • Colorectal cancer rates ranged from 78.9 (East) to 247.5 (Alaska) in males and 74.9 (East) to 244.6 (Alaska) in females.
  • Lung cancer rates ranged from 71.0 (Southwest) to 388.5 (Southern Plains) in males and 44.3 (Southwest) to 390.0 (Northern Plains) in females.
  • Breast cancer rates for AI/AN females were lowest in the Southwest (176.2) and highest in the Southern Plains (408.6).
  • Cervical cancer rates ranged from 8.0 (East) to 21.9 (Southern Plains).

Differences by Year of Diagnosis

Figure 3. Change in Incidence Ratesa of Screening-Detectable Cancersb in AI/ANc Populations, 1999 to 2018

Males
Males
Change in rates
Cancer 1999 2018 Percent Change AAPCd
Colorectal 218.2 129.8 -40.5 -1.2
Lung 254.3 207.4 -18.4 -1.5
Female Breast NA NA NA NA
Cervical NA NA NA NA
Females
Females
Change in rates
Cancer 1999 2018 Percent Change AAPCd
Colorectal 135 104.7 -22.4 -0.8
Lung 179.5 182.6 1.7 NS
Female Breast 292.3 270.6 -7.4 NS
Cervical 18.2 13.4 -26.4 NS

Abbreviations: NA: Not Applicable; NS: Not Significant

aRates are age-adjusted to the 2000 standard U.S. population. The change in rates was calculated as the total percentage change from the rate in 1999 to the rate in 2018.
bAnalysis was limited to cases that met the following age cutoffs: colorectal cancer, 45 or older; lung cancer, 50 or older; female breast cancer, 50 or older; cervical cancer, 20 or older. Single-year age data are not available in the dataset; therefore, the age cutoff for cervical cancer does not reflect the screening recommendation of 21 years.
cAI/AN refers to non-Hispanic American Indian or Alaska Native individuals living in PRCDA counties.
dAAPC refers to annual average percent change, calculated using joinpoint regression. AAPCs reported represent significant changes in cancer incidence trends.

  • Among AI/AN males, lung cancer incidence rates decreased 18% and colorectal cancer incidence rates decreased 41% between 1999 and 2018.
  • Among AI/AN females, colorectal, breast, and cervical cancer incidence rates decreased from 7% to 26% between 1999 and 2018. However, lung cancer incidence rates increased 2% from 1999 to 2018.

Data Sources

Data in this brief come from U.S. Cancer Statistics, the official federal cancer statistics.

U.S. Cancer Statistics incidence data are from population-based registries that participate in CDC’s National Program of Cancer Registries (NPCR) and/or the National Cancer Institute’s Surveillance, Epidemiology, and End Results (SEER) Program and met high-quality data criteria for the 2020 data submission, covering 99% of the U.S. population.

References

1Melkonian SC, Weir HK, Jim MA, Preikschat B, Haverkamp D, White MC. Incidence of and trends in the leading cancers with elevated incidence among American Indian and Alaska Native populations, 2012–2016. American Journal of Epidemiology 2021;190(4):528–538.

2McOliver CA, Camper AK, Doyle JT, Eggers MJ, Ford TE, Lila MA, Berner J, Campbell L, Donatuto J. Community-based research as a mechanism to reduce environmental health disparities in American Indian and Alaska Native communities. International Journal of Environmental Research and Public Health 2015;12(4):4076–4100.

3Warne D, Lajimodiere D. American Indian health disparities: Psychosocial influences. Social and Personality Psychology Compass 2015;9(10):567–579.

4Warne D, Wescott S. Social determinants of American Indian nutritional health. Current Developments in Nutrition 2019;3(Suppl 2):12–18.

5Towne SD, Smith ML, Ory MG. Geographic variations in access and utilization of cancer screening services: examining disparities among American Indian and Alaska Native Elders. International Journal of Health Geographics 2014;13(1):18.

6U.S. Preventive Services Task Force. Cancer Recommendations. Accessed August 2021.

Suggested Citation

Centers for Disease Control and Prevention. Incidence of Screening-detectable Cancers Among American Indian and Alaska Native Populations 2014–2018 (Purchased/Referred Care Delivery Areas). USCS Data Brief, no. 24. Atlanta, GA: Centers for Disease Control and Prevention, US Department of Health and Human Services; 2021.