Comparative modeling of gastric cancer disparities and prevention in the US and globally

Gastric cancer (GC), specifically gastric adenocarcinoma, is the fifth most common cancer and the third leading cause of cancer death globally and has been categorized as a neglected cancer by the World Health Organization. In the U.S., there are stark disparities, with Blacks, Hispanics and Asians having a nearly two- fold greater risk of developing or dying from GC compared to Whites, reflecting differences in risk factors, such as Helicobacter pylori (H. pylori) infection and smoking, as well as access to primary prevention and care. Several factors are changing the landscape of GC prevention, including a better understanding of the disease natural history, new evidence on prevention from prospective studies, and anticipated results from randomized controlled trials. As early GC detection can improve survival by allowing for curative surgical or noninvasive endoscopic resection, new targeted approaches to GC prevention have the potential to markedly improve population health and reduce GC disparities within the U.S. Although H. pylori has been the primary focus of global GC prevention efforts to date, substantial variation by subpopulation in H. pylori prevalence in the U.S. and the world has accentuated the need to optimize H. pylori screen-and-treat interventions for vulnerable groups. One approach is targeted endoscopic screening of high-risk individuals. For instance, persons found to have gastric intestinal metaplasia, a precursor lesion associated with a high progression risk to gastric neoplasia, are recommended to undergo endoscopic surveillance in many countries. A critical need exists to identify effective and cost-effective strategies to address these clinical challenges in the U.S., as well as globally. This proposed work builds upon prior GC work spanning GC and H. pylori simulation modeling studies, GC secondary database analyses, and relevant methodologic and global cancer modeling publications. The research team for this proposal has a vast collective experience in simulation and comparative modeling for cancer control, clinical expertise across the spectrum of GC prevention and care, and a demonstrated track record and commitment to informing cancer care and policy. The proposed three modeling groups are well-positioned to perform and successfully complete the highly relevant project aims. The overarching goal of the proposed research is to produce innovative and paradigm-shifting changes to cancer care through a disparities-focused modeling approach targeting the most vulnerable, high-risk populations that bear the greatest burden of GC in the US, and the world. We will accomplish this goal by performing comparative modeling and completing the following aims: 1) Develop GC simulation models to estimate GC outcomes for subgroups by race and ethnicity in the U.S.; 2) Assess the impact of risk factor trends and primary prevention strategies on GC disparities; 3) Evaluate targeted secondary prevention strategies for reducing early onset-related mortality and GC disparities, and 4) Adapt the models to evaluate GC prevention policies in the global setting.