Wiggins, Charles L.

Abstract Background: Cancer incidence rates for American Indian and Alaska Native (AI/AN) populations vary by geographic region in the United States. The purpose of this study is to examine cancer incidence rates and trends in the AI/AN population compared with the non-Hispanic white population in the United States for the years 2010 to 2015. Methods: Cases diagnosed during 2010 to 2015 were identified from population-based cancer registries and linked with the Indian Health Service (IHS) patient registration databases to describe cancer incidence rates in non-Hispanic AI/AN persons compared with non-Hispanic whites (whites) living in IHS purchased/referred care delivery area counties. Age-adjusted rates were calculated for the 15 most common cancer sites, expressed per 100,000 per year. Incidence rates are presented overall as well as by region. Trends were estimated using joinpoint regression analyses. Results: Lung and colorectal cancer incidence rates were nearly 20% to 2.5 times higher in AI/AN males and nearly 20% to nearly 3 times higher in AI/AN females compared with whites in the Northern Plains, Southern Plains, Pacific Coast, and Alaska. Cancers of the liver, kidney, and stomach were significantly higher in the AI/AN compared with the white population in all regions. We observed more significant decreases in cancer incidence rates in the white population compared with the AI/AN population. Conclusions: Findings demonstrate the importance of examining cancer disparities between AI/AN and white populations. Disparities have widened for lung, female breast, and liver cancers. Impact: These findings highlight opportunities for targeted public health interventions to reduce AI/AN cancer incidence.

Objectives. We used improved data on American Indian and Alaska Native (AI/AN) ancestry to provide an updated and comprehensive description of cancer mortality and incidence among AI/AN populations from 1990 to 2009. Methods. We linked the National Death Index and central cancer registry records independently to the Indian Health Service (IHS) patient registration database to improve identification of AI/AN persons in cancer mortality and incidence data, respectively. Analyses were restricted to non-Hispanic persons residing in Contract Health Service Delivery Area counties in 6 geographic regions of the United States. We compared age-adjusted mortality and incidence rates for AI/AN populations with White populations using rate ratios and mortality-to-incidence ratios. Trends were described using joinpoint analysis. Results. Cancer mortality and incidence rates for AI/AN persons compared with Whites varied by region and type of cancer. Trends in death rates showed that greater progress in cancer control was achieved for White populations compared with AI/AN populations over the last 2 decades. Conclusions. Spatial variations in mortality and incidence by type of cancer demonstrated both persistent and emerging challenges for cancer control in AI/AN populations.

Abstract Cancer incidence for American Indians and Alaska Natives is typically reported as a single rate for all U.S. indigenous populations combined. Previously reported combined rates suggest that American Indians and Alaska Natives have lower cancer incidence rates compared with the U.S. population. Alaska Native people comprise three major ethnic groups: Eskimo, Indian, and Aleut people. We examined cancer incidence from only Alaska Indians and compared incidence rates with an American Indian population living in New Mexico. These data indicate striking differences in cancer patterns between two American Indian populations. Cancer data for the years 1993 to 2002 for American Indians of New Mexico and U.S. Whites are from the National Cancer Institute Surveillance, Epidemiology, and End Results Program Public-use data set. Data for Alaska Indians are from the Alaska Native Tumor Registry, which is also a Surveillance Epidemiology and End Results Program participant. Overall, cancer incidence rates for all sites combined in New Mexico Indian men and women were lower than U.S. White rates, whereas Alaska Indian men and women exceeded U.S. rates. In comparing Alaska and New Mexico Indians, we observed a 2.5-fold higher incidence of cancer among Alaska Indians. The largest differences between the two Indian populations were noted primarily in cancers associated with tobacco use, including cancers of the oral cavity/pharynx, esophagus (only in men), colon and rectum, pancreas, larynx (men), lung, prostate, and urinary bladder (men). Lung cancer rates in Alaska Indian men and women were 7 and 10 times those of New Mexico Indian men and women. (Cancer Epidemiol Biomarkers Prev 2006;15(8):1515–9)