Gastric Cancer Hits American Indian Patients Harder and Treatment Starts Slower in North Carolina

Gastric cancer remains one of the most formidable malignancies in oncology, a disease that is often diagnosed late and treated with difficulty, and a new study from North Carolina now shows that the burden of this cancer is not shared equally across racial groups within the state. Researchers led by Madison T. Uhrin and Bradford E. Jackson of the University of North Carolina at Chapel Hill examined nearly two decades of statewide cancer registry data and found that non-Hispanic American Indian and Alaska Native patients with gastric cancer were diagnosed at a younger age, more frequently with tumors arising outside the upper part of the stomach, and at somewhat later stages than their non-Hispanic white counterparts. Perhaps most strikingly, American Indian patients were consistently slower to begin treatment after diagnosis, with a measurable gap appearing within the first thirty days, a window that oncologists consider critical for effective intervention.

The study, published in the journal Cancer Causes & Control, drew on records from the North Carolina Central Cancer Registry covering the years 2003 through 2021. The investigators constructed two analytic cohorts: a diagnosis cohort comprising 111 non-Hispanic American Indian and Alaska Native patients and 7,685 non-Hispanic white patients, and a treatment cohort of 97 American Indian and Alaska Native patients and 6,040 white patients for whom treatment information was available. By restricting the analysis to North Carolina and comparing the two groups directly, the team aimed to provide the first baseline assessment of the gastric cancer burden borne by American Indian communities in the state, a population that has historically been undercounted and understudied in cancer surveillance research.

The demographic and clinical profile of gastric cancer differed markedly between the two groups. American Indian and Alaska Native patients were diagnosed at a median age of 65 years compared with 68 years for white patients, a difference that was statistically significant. The anatomical distribution of their tumors also diverged: 80 percent of American Indian and Alaska Native patients had non-cardia gastric cancer, tumors arising in the lower portions of the stomach, whereas the corresponding figure among white patients was 62 percent. This distinction matters clinically because cardia and non-cardia gastric cancers have different risk factor profiles, different patterns of occurrence across populations, and different associations with infection by the bacterium Helicobacter pylori, a well-established cause of gastric carcinoma.

Stage at diagnosis also differed, with 36 percent of American Indian and Alaska Native patients diagnosed at a later stage compared with 32 percent of white patients, a modest but statistically significant difference. The two groups differed just as sharply in where they lived. Fully 76 percent of American Indian and Alaska Native patients resided in areas with low residential population density, compared with only 26 percent of white patients. This rural concentration is more than a descriptive footnote; rural residence is associated with longer travel distances to specialized cancer centers, reduced access to gastroenterologists and oncologists, and documented delays in cancer diagnosis and treatment across many malignancies. Any explanation of the treatment gaps observed in this study must contend with the geography of the affected communities.

To quantify the treatment disparity, the researchers analyzed the risk of receiving no documented treatment at all and the timing of the first treatment after diagnosis. Using modified Poisson regression, a statistical technique well suited to modeling common binary outcomes while estimating risk ratios directly, they estimated the multivariable-adjusted association between race and failure to initiate treatment. The adjusted risk ratio was 1.13, with a 95 percent confidence interval spanning 0.87 to 1.47 and a p-value of 0.34. In other words, American Indian and Alaska Native patients had a point estimate suggesting a thirteen percent higher risk of receiving no treatment, but the wide confidence interval means the data cannot rule out effects ranging from a modest reduction to a nearly fifty percent increase in risk. The authors were careful to present this result as inconclusive rather than as evidence of no difference.

The timing analysis told a more consistent story. The team estimated race-specific cumulative incidence functions for treatment initiation, a method that accounts for the possibility that some patients die before starting treatment, and refined these estimates using inverse probability weighting to adjust for key covariates such as age, stage, and socioeconomic characteristics of the patients’ residential areas. Confidence intervals were obtained through bootstrapping, a resampling approach that makes minimal assumptions about the underlying distributions. The cumulative incidence of treatment initiation was consistently lower for American Indian and Alaska Native patients throughout follow-up, and at thirty days after diagnosis the difference was statistically significant, with a cumulative incidence difference of minus 0.09 and a 95 percent confidence interval of minus 0.17 to minus 0.01. Nine percentage points fewer American Indian and Alaska Native patients had begun treatment within the first month.

Why does a thirty-day delay matter? In gastric cancer, as in many solid tumors, time to first treatment is a widely used quality-of-care indicator, and delays are associated with disease progression, reduced eligibility for curative surgery, and worse survival. A nine-percentage-point gap in the first month, sustained across the first year after diagnosis, suggests a systematic difference in how quickly patients move from diagnosis to oncologic care, whether because of barriers in referral pathways, insurance and authorization hurdles, transportation and lodging challenges in rural areas, patient-provider communication, or differences in tumor biology and comorbid illness that complicate treatment planning. The study was not designed to isolate which of these mechanisms dominates, but the consistency of the timing gap, in contrast to the imprecise estimate for receiving no treatment at all, points toward delays rather than outright withholding of care as the central disparity.

The findings fit into a broader national picture. Previous research has documented elevated gastric cancer incidence and mortality among American Indian and Alaska Native populations in the United States, with particularly high rates in Alaska and certain regions of the country, and prior work has linked these patterns to higher prevalence of Helicobacter pylori infection and its virulent strains in some Native communities. The North Carolina study extends this literature by focusing on a state with a large, diverse Native population that includes both federally and non-federally recognized tribes, and by adding the dimension of treatment timeliness, which had been examined nationally but not previously at the state level for this population. The authors also situate the work within a series of recent North Carolina analyses of cancer burden and end-of-life care quality among American Indian patients conducted with the Cancer Information and Population Health Resource at the UNC Lineberger Comprehensive Cancer Center.

The researchers acknowledge important limitations inherent to registry-based studies of Native populations. Racial misclassification is a persistent problem in state cancer data; earlier work in North Carolina has shown that American Indian race is sometimes misrecorded among members of non-federally recognized tribes, which could bias incidence and outcome estimates in either direction. Registry treatment information may also be incomplete, particularly for care delivered outside reporting facilities, and the modest number of American Indian and Alaska Native patients, 111 in the diagnosis cohort, limits statistical power and explains the wide confidence interval around the risk ratio for no treatment. The investigators addressed the treatment-data concern by noting prior validation work on registry-based treatment information and by using documented receipt of treatment as the outcome, while the small-sample problem was handled through robust variance estimation and bootstrapped intervals rather than ignored.

For public health practitioners and oncologists in North Carolina and beyond, the study delivers a clear message: gastric cancer in American Indian and Alaska Native communities presents differently, is caught later, and reaches treatment more slowly than in the white population, and these differences are measurable with the surveillance systems already in place. The authors frame their results as a baseline against which future interventions can be judged, whether those interventions target earlier detection of non-cardia tumors in younger Native patients, streamline the diagnostic-to-treatment pathway in rural counties, or expand culturally grounded patient navigation. Given that gastric cancer is often preventable through detection and eradication of Helicobacter pylori and that survival depends heavily on stage at diagnosis, closing the thirty-day treatment gap identified here could translate into concrete survival gains for a population that has carried a disproportionate share of this disease for far too long.

Subject of Research: Racial disparities in gastric cancer diagnosis and time-to-first-treatment between non-Hispanic American Indian Alaska Native and white patients in North Carolina

Article Title: Characterizing gastric cancer and time-to-first treatment among non-Hispanic American Indian Alaska Native and white patients in North Carolina

Article References: Uhrin, M. T., Jackson, B. E., Baggett, C. D., Spees, L. P., Begay, J. A., Epplein, M., Wheeler, S. B., Bell, R. A., & Emerson, M. A. (2026). Characterizing gastric cancer and time-to-first treatment among non-Hispanic American Indian Alaska Native and white patients in North Carolina. Cancer Causes & Control, 37(10), Article 173. https://doi.org/10.1007/s10552-026-02254-w

Image Credits: AI Generated

DOI: 10.1007/s10552-026-02254-w

Keywords: gastric cancer, American Indian, Alaska Native, health disparity, time to treatment, North Carolina, cancer registry, Helicobacter pylori, non-cardia gastric cancer, rural health, cancer epidemiology, Cancer Causes & Control