AUTHOR=Petrick Jessica L. , Barber Lauren E. , Warren Andersen Shaneda , Florio Andrea A. , Palmer Julie R. , Rosenberg Lynn 

TITLE=Racial Disparities and Sex Differences in Early- and Late-Onset Colorectal Cancer Incidence, 2001–2018

JOURNAL=Frontiers in Oncology

VOLUME=Volume 11 - 2021

YEAR=2021

URL=https://www.frontiersin.org/journals/oncology/articles/10.3389/fonc.2021.734998

DOI=10.3389/fonc.2021.734998

ISSN=2234-943X

ABSTRACT=Background: Colorectal cancer (CRC) incidence rates have increased in younger individuals worldwide. We examined the most recent early- and late-onset CRC rates for the US. 
Methods: Age-standardized incidence rates (ASIR, per 100,000) of CRC were calculated using the US Cancer Statistics Database’s high-quality population-based cancer registry data from the entire US population. Results were cross-classified by age (20-49 [early-onset] and 50-74 years [late-onset]), race/ethnicity (non-Hispanic White, non-Hispanic Black, Hispanic, American Indian/Alaskan Native, Asian/Pacific Islander), sex, anatomic location (proximal, distal, rectal), and histology (adenocarcinoma, neuroendocrine). 
Results: During 2001 through 2018, early-onset CRC rates significantly increased among American Indian/Alaskan Natives, Hispanics, and Whites. Compared to Whites, early-onset CRC rates are now 21% higher in American Indian/Alaskan Native and 6% higher in Blacks. Rates of early-onset colorectal neuroendocrine tumors have increased in White, Blacks, and Hispanics; early-onset colorectal neuroendocrine tumor rates are 2-times higher in Blacks compared to Whites. Late-onset colorectal adenocarcinoma rates are decreasing, while late-onset colorectal neuroendocrine tumor rates are increasing, in all racial/ethnic groups. Late-onset CRC rates remain 29% higher in Blacks and 15% higher in American Indian/Alaskan Natives compared to Whites. Overall, CRC incidence was higher in men than women, but incidence of early-onset distal colon cancer was higher in women. 
Conclusions: The early-onset CRC disparity between Blacks and Whites has narrowed, due to increasing rates in Whites—rates in Blacks have remained stable. However, rates of colorectal neuroendocrine tumors are increasing in Blacks. Blacks and American Indian/Alaskan Native have the highest rates of both early- and late-onset CRC. 
Impact: Ongoing prevention efforts must ensure access to and uptake of CRC screening for Blacks and American Indian/Alaskan Natives.