Abstract Despite the tremendous advances in cancer prevention and treatment strategies that have been achieved since the war on cancer plan in the 1970’s, it is clear that not all communities are equally benefiting from such advances and that minority populations nearly always have worse cancer health outcomes. These cancer health disparities are the result of complex interactions between social determinants of health, population-specific cultural behaviors and lifestyles, and unique biological differences that associate with ancestry. Two major limitations to the advancement of precision medicine in minority groups include the lack of: i) race/ethnic appropriate genomic data, which will facilitate identifying priority targets for therapeutic development, and ii) patient-derived models, such as patient-derived xenografts (PDXs) that recapitulate the unique interactions of germline and somatic genetics that exist in minority patients. In this presentation we describe the development of an analytical pipeline to quantify continental genetic ancestry that we have developed for the Cancer Genomics Cloud as part of the PDX Development and Trials Center Research Network (PDXnet). This pipeline leverages a novel reference panel for the program SNPweights, which includes a greater representation of genomic data from Native and Latin American populations than previously published reference panels, and thus provides improved assignment of American continental ancestry. We use this pipeline to characterize the diversity of the PDX models in PDXnet, which represent a manifold increase in models with African and American continental genetic ancestry compared with those available in other public resources. Finally, we present power analyses to demonstrate that additional PDX models derived from patients from minority populations are critically needed to effectively address health equity goals in the US. Citation Format: Brian J. Sanderson, Paul Lott, Anuj Srivastava, PDXNet Consortium, Jeffrey H. Chuang, Luis G. Carvajal-Carmona. Addressing cancer health disparities among US minority populations with patient-derived xenografts [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1915.