Examining Cancer Survival Disparities in Urban American-Indian and Alaskan Natives

Study: Urban native populations may have decreased survival following invasive prostate and breast cancer.

Urban American Indians and Alaskan Natives (AIAN) appear to have lower survival rates following invasive prostate and breast cancer as compared to urban non-Hispanic whites (NHW), according to a recent study published in Cancer Research, a journal of the American Association for Cancer Research (AACR).

Disparities between Native Americans and other groups have persisted for centuries,
research has shown. Life expectancy for AIANs born today is more than four years shorter than that of the average American.

Moreover, the most recent data from the Indian Health Service (IHS) shows that AIANs have higher rates of mortality as compared to the general American population in many categories including accidents, diabetes, liver diseases, and alcohol.

Cancer is among the areas of health where Native Americans experience considerable disparities.

“It’s been reported that the AIAN community has a higher cancer burden than other racial/ethnic groups,” said lead author Marc A. Emerson, MPH, PhD candidate, Department of Epidemiology, University of North Carolina at Chapel Hill. “However, accurate, population-based information on the cancer experience for this population residing in an urban setting is severely lacking.”

To overcome that problem, Emerson worked with senior author Laurel A. Habel, PhD, associate director for cancer research at the Kaiser Permanente Northern California (KPNC) Division of Research and utilized data from KPNC, a health care system located in California.

Enrollees of the study, which included 582 AIAN and 82,696 NHW participants, were diagnosed with primary invasive breast, prostate, lung, or colorectal cancer.

This study compared cancer survival among the two urban populations. Emerson and colleagues found that the AIAN community were 87 percent more likely to die from prostate cancer after their diagnosis of invasive prostate cancer. They also found that members of the AIAN population were 47 percent more likely to die following an invasive breast cancer diagnosis. Even after adjusting for income, the outcomes were not significantly changed. The researchers did not find statistically significant disparities among those with lung or colorectal cancer.

“Our results suggest that factors other than health insurance and income may play a role in the survival differences observed for breast and prostate cancer,” said Emerson. He speculated that the tumor biology between AIANs and NHWs could be different, or that perhaps these two populations have differences in adherence to treatment.