Stomach Cancer Incidence and Mortality Trends among Circumpolar Nations

Characterizing Cancer Burden in the American Indian Population in North Carolina

BACKGROUND

The American Indian (AI) population in North Carolina has limited access to the Indian Health Service. Consequently, cancer burden and disparities may differ from national estimates. We describe the AI cancer population and examine AI-White disparities in cancer incidence and mortality.

METHODS

We identified cancer cases diagnosed among adult AI and White populations between 2014 and 2018 from the North Carolina Central Cancer Registry. We estimated incidence and mortality rate ratios (IRR and MRR) by race. In addition, between the AI and White populations, we estimated the ratio of relative frequency differences [RRF, with 95% confidence limits (CL)] of clinical and sociodemographic characteristics. Finally, we evaluated the geographic distribution of incident diagnoses among AI populations.

RESULTS

Our analytic sample included 2,161 AI and 204,613 White individuals with cancer. Compared with the White population, the AI population was more likely to live in rural areas (48% vs. 25%; RRF, 1.89; 95% CL, 1.81-1.97) and to have Medicaid (18% vs. 7%; RRF, 2.49; 95% CL, 2.27-2.71). Among the AI population, the highest age-standardized incidence rates were female breast, followed by prostate and lung and bronchus. Liver cancer incidence was significantly higher among the AI population than White population (IRR, 1.27; 95% CL, 1.01-1.59). AI patients had higher mortality rates for prostate (MRR, 1.72; CL, 1.09-2.70), stomach (MRR, 1.82; 95% CL, 1.15-2.86), and liver (MRR, 1.70; 95% CL, 1.25-2.33) cancers compared with White patients.

CONCLUSIONS

To reduce prostate, stomach, and liver cancer disparities among AI populations in North Carolina, multi-modal interventions targeting risk factors and increasing screening and treatment are needed.

IMPACT

This study identifies cancer disparities that can inform targeted interventions to improve outcomes among AI populations in North Carolina.

The Alaska Native Tumour Registry: fifty years of cancer surveillance data for Alaska Native people

Like other Indigenous Circumpolar populations, Alaska Native (AN) people experience different patterns of cancer than their non-Indigenous counterparts. Every 5 years, the Alaska Native Tumour Registry releases a comprehensive report on cancer among AN people; this study provides 50 years of cancer surveillance data. Five-year annual-average age-adjusted incidence rates were calculated for time-periods ranging 1969-2018. AN data were compared with data for US whites (SEER 9). Mortality rates were calculated for 1994-2018 using data from the National Center for Health Statistics. During 2014-2018, there were 2,401 cases of invasive cancer among AN people. Among these, the most commonly diagnosed cancers were colorectal (405 cases, 17% of all cancers), lung and bronchus (373 cases, 16% of all cancers), and female breast (340 cases, 14% of all cancers). Lung cancer was the leading cause of cancer death, followed by colorectal and female breast cancers. These leading cancers are screenable, and preventable through lifestyle modifications including tobacco cessation, healthy eating and engaging in physical activity. These data provide important information to support cancer prevention and control among AN people. Cancer surveillance has been a valuable tool throughout the Circumpolar North to support reducing the burden of cancer among Indigenous populations.Abbreviations: ANAI: Alaska Native/American Indian; AN: Alaska Native; USW: U.S. White(s); ANMC: Alaska Native Medical Center; ANTR: Alaska Native Tumour Registry; IR: Incidence Rate; CI: Confidence Interval; RR: Rate Ratio; ICD-O-3: International Classification of Diseases for Oncology - Third Edition; SEER: Surveillance, Epidemiology and End Results.

Impact of Medicaid Expansion on Incidence and Mortality from Gastric and Esophageal Cancer

BACKGROUND AND AIMS

Individuals in Medicaid expanded states have increased access to treatment for medical conditions and other health care resources. Esophageal and gastric cancer are associated with several modifiable risk factors (e.g. smoking, drinking, Helicobacter pylori infection). The impact of Medicaid expansion on these cancers incidence and mortality remains uninvestigated.

METHODS

We evaluated the association between Medicaid expansion and gastric and esophageal cancer incidence and mortality in adults aged 25-64. We employed an observational design using a difference-in-differences method with state level data, from 2010 to 2017. Annual, age-adjusted gastric and esophageal cancer incidence and mortality rates, from the CDC Wonder Database, were analyzed. Rates were adjusted for by several socio-demographic factors.

RESULTS

Expansion and non-expansion states were similar in percent Hispanic ethnicity and female gender. The non-expansion states had significantly higher proportion of Black race, diabetics, obese persons, smokers, and those living below the federal poverty line. Adjusted analyses demonstrate that expansion states had significantly fewer new cases of gastric cancer: - 1.6 (95% CI 0.2-3.5; P = 0.08) per 1,000,000 persons per year. No significant association was seen between Medicaid expansion and gastric cancer mortality (0.46 [95% CI - 0.08 to 0.17; P = 0.46]) and esophageal cancer incidence (0.8 [95% CI - 0.08 to 0.24; P = 0.33]) and mortality (1.0 [95% CI - 0.06 to 0.26; P = 0.21]) in multivariable analyses.

CONCLUSION

States that adopted Medicaid expansion saw a decrease in gastric cancer incidence when compared to states that did not expand Medicaid. Though several factors may influence gastric cancer incidence, this association is important to consider during health policy negotiations.

Native and Indigenous Populations and Gastric Cancer: A Worldwide Review

Gastric cancer is a worldwide concern, particularly for Indigenous populations who face greater disparities in healthcare. With decreased access to screening and critical treatment delays, this group is experiencing adverse health effects. To determine what factors drive these disparities, a systematic review was performed in PubMed. This revealed a lack of research on gastric cancer specific to this population. The literature primarily focused on subset analyses and biological aspects with sparse focus on determinants of health. The results informed this presentation on factors related to Indigenous gastric cancer, which are influenced by colonialism. Indigenous populations encounter high rates of food shortage, exposure to harmful environmental agents, structural racism in the built environment, H. pylori, and compromised healthcare quality as an effect of colonialism, which all contribute to the gastric cancer burden. Putting gastric cancer into a cultural context is a potential means to respond to colonial perspectives and their negative impact on Indigenous patients. The objective of this manuscript is to examine the current state of gastric cancer literature from a global perspective, describe what is currently known based on this literature review, supplemented with additional resources due to lack of published works in PubMed, and to present a model of gastric cancer through the lens of a modified medicine wheel as a potential tool to counter colonial healthcare perspectives and to honor Indigenous culture.