Abstract 802: Molecular profile of gastric cancer in Hispanics living in Puerto Rico

Abstract Gastric cancer (GC) is the 4th leading cause of cancer death globally. The incidence and mortality rates of GC differ dramatically between racial/ethnic groupings. In the United States (U.S.), Hispanics, non-Hispanic Blacks, and Asian or Pacific Islanders are more likely to be diagnosed with GC and have a higher mortality rate than non-Hispanic Whites. Among the Hispanic population living in Puerto Rico (PRH), GC ranks among the top ten leading causes of cancer death, whereas this malignancy is not a major cause of cancer mortality in the mainland U.S. Tumor profiling approaches have resulted in the discovery of actionable gene alterations, which serve as a guide for treatment strategies and ultimately enhance the overall survival rates of individuals diagnosed with cancer. However, descriptive information regarding the genetic mutational landscape of GC tumors from PRH is limited. This study aims to describe the genomic profile of GC tumors in PRH and to identify the most prevalent genetic mutations. We retrospectively examined GC tumor mutational profiles from 106 PRH that underwent NGS testing from 2015 to 2022 (provided by CARIS Life Sciences and the Precision Oncology Alliance). We compared PRH GC tumor somatic mutation prevalence to TCGA and the AACR Project Genomics Evidence Neoplasia Information Exchange (GENIE), both available through the cBioPortal for Cancer Genomics. Descriptive statistics were performed to characterize the database. Among the top mutated genes for GC tumors in PRH were TP53 (54.1%, n=85), ARID1A (34.2%, n=73), KMT2D (30.5%, n=82), CDH1 (29.4%, n=85) and ZFHX3 (27.3%, n=55). The most frequent gene amplifications were ERBB2 (7.1%, n=84), KRAS (6.0%, n=84), and CCNE1 (4.9%, n=81). Compared to other datasets, PRH had significantly different mutational frequencies of GC driver genes like TP53, ARID1A, CDH1, and KMT2D. This study is the first to report PRH GC tumor mutational profiles and compare the mutational frequencies to other non-Hispanic and U.S. mainland Hispanic populations using TCGA and GENIE data sets. Furthermore, our study provides data on the specific mutational landscape for Hispanics with GC and the implications on therapeutic options and clinical outcomes. Developing new treatments for genomically diverse populations requires understanding the most common carcinogenic molecular pathways that affect Hispanics with GC. Citation Format: Ingrid Montes-Rodriguez, Hilmaris Centeno-Girona, Noridza Rivera, Marcia Cruz-Correa. Molecular profile of gastric cancer in Hispanics living in Puerto Rico [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 802.