E0682 - The Disproportionate Rise of Non-Cardia Primary Gastric Cancer Incidence Rates in Younger Women Is Driven by Black and White Race but Not Asian Race: A Population-Based Time-Trend Analysis Using the USCS Database

Tuesday, October 25, 2022

3:00 PM – 5:00 PM ET

Location: Crown Ballroom

Presenting Author(s)

Yazan Abboud, MD

Cedars-Sinai Medical Center
Los Angeles, CA

Introduction: Recent population-based time-trend analysis of US nationwide databases showed a disproportional increase in non-cardia gastric cancer (NCGC) incidence rates in younger women (< 55 years) compared to counterpart men. However, the impact of race on the increasing trend in younger women has not been evaluated. Therefore, the aim of this study was to conduct sex and age-specific analysis of NCGC incidence rates among different race groups in a nationally representative US database.

Methods: NCGC incidence rates per 100,000 population were obtained from the United States Cancer Statistics (USCS) database and were age-adjusted to the 2000 US population using SEER*Stat software (v8.4.1, NCI) between 2001-2018. The rates were stratified by age and sex and evaluated in patients of White, Black, and Asian races. Time trends of incidence rates were computed using Joinpoint Regression Software (v4.9.0.1, NCI) utilizing Monte Carlo Permutation analysis to identify the simplest segmented trend. Annual percentage change (APC) and average APC (AAPC) were estimated. Sex-specific pairwise comparison was conducted to assess identicalness and parallelism between the trends and the absolute AAPC difference was evaluated. Further age and sex-specific analysis was conducted in older (³55 years) and younger adults (< 55 years). A p-value cutoff of 0.05 was utilized.

Results: A total of 169,517 patients were diagnosed with NCGC between 2001-2018 (45.4% women). Among Whites (11,991 patients; 47.4% women), incidence rates were decreasing in the overall age group and in older adults in both sexes. However, in younger White adults (17,790 patients; 49.9% women), incidence rates were increasing in women (AAPC=3.19, p< 0.001) at a significantly greater rate than in men (AAPC=1.58, p< 0.001) with an absolute AAPC difference of 1.60, p< 0.001. Similar results were seen in Black patients with a greater absolute AAPC difference between younger Black women and men (2.23, p< 0.001). Among Asian adults (16,132 patients; 46.4% women), there was no statistical difference in trends between women and men in all age groups (Table and Figure).

Discussion: Nationwide data from the USCS database, covering ≈100% of US population, showed a greater increase in NCGC incidence among younger White and Black women compared to counterpart men. However, this disproportionate increase was not seen in the Asian race. Future research should aim to evaluate risk factors for the increasing trend in younger women.