Abstract 6227: Contemporary incidence of gastroesophageal junction and gastric cancers in the United States, 2016-2021

Abstract Background: Limited data are available on the contemporary incidence of gastroesophageal junction cancer (GEJC) and gastric (GC). This study aimed to examine the incidence rates and trends of GEJC and GC overall and by gender and race/ethnicity. Methods: In this cross-sectional study, we used 2016-2021 data from the U.S. Epidemiology, and End Results (SEER) 22 registries. Per the primary International Classification of Diseases for Oncology, 3rd Edition (ICD-O-3) used by SEER, GEJC cases were identified by “C16.0 Cardia” under GC “C16 Stomach”. Age-adjusted incidence rates were calculated using the SEER*Stat software, and annual percentage change (APC) in incidence was analyzed using the Joinpoint regression program. Results: During 2016-2021, 17,959 GEJC and 65,899 GC cases were identified. For both cancer types, the age-adjusted incidence rate was higher in men than in women (4.42 vs. 1.16 per 100,000/year for GEJC; 12.83 vs. 7.58 per 100,000/year for GC). By race and ethnicity, for GEJC, non-Hispanic white people had the highest rates of new cancer diagnoses (3.05 per 100,000/year) while non-Hispanic black people had the lowest (1.79 per 100,000/year). For GC, non-Hispanic black people had the highest rates of new cancer diagnoses (13.81 per 100,000/year) while non-Hispanic white people had the lowest (7.61 per 100,000/year). By race/ethnicity and gender, the highest incidence rate of GEJC was found among non-Hispanic white men (5.17 per 100,000 person /year). The highest incidence rate of GC was found among the non-Hispanic black men (18.29 per 100,000/year). From 2016 to 2021, there were no significant changes in both GEJC and GC incidence rates overall and by gender, and race/ethnicity. However, when limiting the analysis to more recent years between 2018 and 2021, there was a falling trend in GEJC but a rising trend in GC incidence overall (APC of -4.08% for GEJC and 3.00% for GC) and by gender (APC of -3.67% for GEJC male and -5.69% for GEJC female; 1.61% for GC male and 4.75 % for GC female). The incidence of GEJC among non-hispanic white men and GC among non-Hispanic black men remained stable. Conclusion: This population-based study highlights the gender and racial/ethnic differences in GEJC and GC incidence in the United States. Ongoing efforts in increasing awareness, prevention, diagnostic, and treatment strategies for these cancers are needed, particularly for sub-populations with the highest incidence. Future studies should investigate the underlying reasons for the increasing trend in gastric cancer. Citation Format: Jessie T. Yan, Alexander Wu, Hongyu Wu, Margarita Kouzova, Steven P. Stratton. Contemporary incidence of gastroesophageal junction and gastric cancers in the United States, 2016-2021 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 6227.