Abstract C080: Race and ethnicity differences in gastrointestinal tumours in the United States, 1992 – 2018
Authors: Filho Adalberto M. , Rosenberg Philip S. , Figueroa Jonine S. 
Published: December 2023

Introduction Over the last decades, studies have suggested a shift in the epidemiological pattern for cancer among young adults (35 – 50 years of age), characterized by an increased incidence of some cancer types that were previously common in older adults (&gt;50). Different racial and ethnic groups may also experience disparities in these cancers. We aimed to assess temporal trends in gastrointestinal (GI) cancer incidence in the United States by cancer site race and ethnicity, age, and sex, to provide possible etiologic clues that might be important for future follow-up in epidemiologic studies. Methods The number of cancer cases and population-at-risk by sex, age (35-84 years old), and race/ethnicity were retrieved from SEER 13 from 1992 to 2018. We included eight GI cancers associated with obesity: colon, rectum, esophagus (adenocarcinoma), gallbladder, gastric (cardia), kidney, liver, and pancreas. For each age group, sex, race, and ethnicity [non-Hispanic White (NHW), non-Hispanic Black (NHB), Hispanic (HIS), Asian, and Pacific Islander (API)], we fitted temporal trends over the period of study and the Estimated Annual Percent Change (EAPC). We visualized trends in age-specific incidence rates by the 2-year age group and 1-year period using Local Drifts (Annual Percent Change, APC) and reported age-standardized rates per 100,000. Results In total, 735780 new cases of GI cancer were diagnosed in the period 1992–2018, 58% males and 42% females. Males had a greater incidence compared to females. Male NHB had the highest incidence rates for colon cancer (72.3), kidney cancer (41.0), pancreas, and liver cancer (24.9 and 21.1, respectively). Overall, colon and rectum cancers have been marked by an increase, followed by a steady decrease for all races and ethnicities and in both sexes in the most recent period evaluated, circa 2007–2018, ranging from -3.73% in API to -1.56 in HIS females. Gallbladder has also decreased over the period for both sexes and broad race ethnicity groups included. Kidney cancer has similarly decreased in men, HIS (-4.32), NHB (-2.47), and NHW (-2.56) during the previous decade while increasing in females (1.91, 2.16, and 2.62, respectively). Local drifts showed that the APC for most GI malignancies is growing for young adults in all race-ethnicity groups and either increasing or steady for older adults from (1992-2018), except for colon and rectum, which had decreased rates for older adults. Conclusion Despite progress in decreasing rates for the last 10 years, the average incidence of most GI malignancies has increased, particularly among young adults. The reported differences in GI by race and ethnicity need to be better investigated in further studies to determine how variations in risk factors exposures (e.g., infection, obesity, alcohol) and opportunistic screening in the younger population might differ between race and ethnic groups.

Citation Format: Adalberto M. Filho, Philip S. Rosenberg, Jonine S. Figueroa. Race and ethnicity differences in gastrointestinal tumours in the United States, 1992 – 2018 [abstract]. In: Proceedings of the 16th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2023 Sep 29-Oct 2;Orlando, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2023;32(12 Suppl):Abstract nr C080.