Abstract B73: Trends in racial disparities in cancer incidence among white and black older adults in the United States

Abstract

Abstract Background: As cancer occurs more commonly in older adults (≥65 years), the aging of the U.S. population is expected to markedly increase the number of cancer diagnoses. Despite this increase, older adults are an understudied cancer patient population. Few studies have reported trends in cancer incidence rates among older adults in the U.S., however, none have examined trends in racial disparities in cancer incidence in this population. Purpose of the study: To examine potential racial disparities in cancer incidence over time among older adults using data from the Surveillance, Epidemiology, and End Results (SEER) Program of the National Cancer Institute. Methods: Cases of female breast, prostate, colorectal, and lung and bronchus cancer were reported to one of 18 SEER registries. Differences in cancer incidence rates by race and changes in these differences over time were examined for cases aged ≥65 years diagnosed 1973-2013. Results: From 1973-2013, lung and bronchus and female breast cancer incidence rates increased while colorectal cancer incidence rates decreased among older adults. Prostate cancer incidence rates increased between 1973 and the mid-nineties and then decreased until 2013 among older adults. Among older women diagnosed with breast cancer, white women had higher incidence rates than black women; however, the percent difference in rates decreased from 23.4% in 1973-1977 to 6.3% in 2008-2013. For prostate cancer, black older men had higher prostate cancer incidence rates than white men from 1973-2013. The percent difference in prostate cancer incidence rates between white and black older men remained relatively large over time, from 45.9% in 1973-1977 to 50.1% in 2008-2013. From 1973-1992, white older adults had higher colorectal incidence rates than black older adults. Notably, beginning in 1993, the colorectal cancer incidence rates among black older adults surpassed those of white older adults. The percent difference in the colorectal cancer incidence rates between white and black older men increased from 4.3% in 1993-1997 to 18.1% in 2008-2013. Lastly, from 1973-2013, black older adults had higher lung and bronchus cancer incidence rates than white older adults. The percentage difference for the rates between white and black older adults decreased from 11.9% in 1973-1977 to 8.5% in 2008-2013. Conclusion: There are considerable racial disparities in cancer incidence rates in the U.S. among older adults. Continued efforts involving cancer prevention are needed to reduce these disparities. Citation Format: Jessica L. Krok-Schoen, James L. Fisher, Ryan D. Baltic, Electra D. Paskett. Trends in racial disparities in cancer incidence among white and black older adults in the United States. [abstract]. In: Proceedings of the Ninth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2016 Sep 25-28; Fort Lauderdale, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2017;26(2 Suppl):Abstract nr B73.