Racial, Ethnic Disparities Persist in Mortality for Patients With Early-Onset CRC

The burden of mortality in early-onset colorectal cancer (EOCRC) was felt the most in non-Hispanic Black patients and Native Hawaiian and Other Pacific Islander patients, according to a new study published in JAMA Network Open,¹ highlighting the ongoing disparities in mortality based on race and ethnicity that exist in EOCRC.

CRC is considered early onset when the patient is diagnosed before age 50 years. CRC remains the second leading cause of death related to cancer in the US,² which makes the increasing incidence of EOCRC all the more important to address. Studies on the burden of EOCRC have lacked data on Asian American and Native Hawaiian and Other Pacific Islander patients. This current study used the California Cancer Registry (CCR) to evaluate the risk of mortality in patients with EOCRC based on race, ethnicity, and social determinants of health at the individual and neighborhood levels.

Racial and ethnic disparities still persist in early-onset colorectal cancer. | Image credit: Sebastian Kaulitzki - stock.adobe.com

The CCR was used to identify patients with CRC and included clinical, demographic, outcome, and treatment data. All patients aged 18 to 49 years diagnosed with primary invasive CRC from January 1, 2000, to December 31, 2019, were included in the study. Diagnosis date, age of diagnosis, race, ethnicity, tumor stage, tumor location, tumor size, and insurance status were gleaned from data in the CCR.

Patients (N = 22,834) were classified into the following ethnic subgroups: Asian American (15.5%), Hispanic (30.2%), Native Hawaiian or Other Pacific Islander (0.6%), non-Hispanic American Indian or Alaska Native (0.5%), non-Hispanic Black (7.3%), and non-Hispanic White (45.9%). Follow-up data were available through December 31, 2019, or death, with follow-up time calculated as number of deaths from diagnosis to earliest date of death or December 31, 2019. All but the Native Hawaiian or Other Pacific Islander group had smaller female counts compared with male, making the overall cohort 46.5% women with a median (IQR) age of 44 (39-47) years.

A higher likelihood of EOCRC mortality was found in Native Hawaiian individuals compared with non-Hispanic White persons (adjusted HR [aHR], 1.69; 95% CI, 1.27-2.23) after adjusting for clustering. Individuals who identified as non-Hispanic Black also had a higher risk of mortality compared with those who identified as non-Hispanic White (aHR, 1.18; 95% CI, 1.07-1.29) after full adjustment. Southeast Asian individuals had the highest mortality risk compared with non-Hispanic White individuals (aHR, 1.29; 95% CI, 1.13-1.46) after disaggregating the Asian American cohort.

When adding neighborhood socioeconomic status (SES) to the model, the association with mortality in EOCRC in Hispanic individuals was not present compared with non-Hispanic White individuals (aHR, 1.00; 95% CI, 0.94-1.06). A small attenuation in mortality likelihood was found when adding neighborhood SES to the model to compare Native Hawaiian individuals with non-Hispanic White individuals (aHR, 1.34; 95% CI, 1.03-1.76), and non-Hispanic Black individuals compared with non-Hispanic White individuals (aHR, 1.27; 95% CI, 1.16-1.40).

There were some limitations to this study. There was a relatively short length of follow-up due to the data being more recent, and the sample sizes were low in some racial and ethnic groups. Underestimation of mortality risk was also possible due to prior studies having found that survival studies could miss deaths in Hispanic and Asian adults. Misclassification of race and ethnicity was possible due to inherent limitations in cancer registry data, and disaggregation did not occur in the Hispanic group. Generalizability may be limited.

Racial and ethnic disparities persist in EOCRC, particularly in Native Hawaiian and Other Pacific Islander individuals and non-Hispanic Black individuals. Social determinants of health likely play the biggest role in determining mortality related to EOCRC, which indicates that the barriers to care need to be addressed to prevent mortality in the future.

References

1. Demb J, Gomez SL, Canchola AJ, et al. Racial and ethnic variation in survival in early-onset colorectal cancer. JAMA Netw Open. 2024;7(11):e2446820. doi:10.1001/jamanetworkopen.2024.46820

2. Colorectal cancer: key facts. World Health Organization. July 11, 2023. Accessed November 22, 2024. https://www.who.int/news-room/fact-sheets/detail/colorectal-cancer