Ethnic Disparities Identified in Colorectal Cancer Diagnoses, Study Finds

Significant disparities in colorectal cancer (CRC) diagnosis exist among ethnic groups, according to a study analyzing data from the English National Health Service (NHS).¹ The findings reveal stark differences, with early-onset CRC being most prevalent among mixed and multiple ethnic groups and least common in White individuals.

Study provides insights that underscore the critical need for equitable CRC screening and diagnostic pathways to address ethnic disparities and improve outcomes. | Image credit: SewcreamStudio - stock.adobe.com

This large, population-based study is published in BMJ Open Gastroenterology.

“If ethnic inequalities are identified then it is vital to describe them in detail in order to tackle them and optimize diagnostic pathways, especially in non-White populations,” wrote the researchers of the study.

While overall CRC rates have decreased in recent years with the help of higher screening rates and earlier detection, rates among Black individuals in the US are higher compared with other groups.² Black individuals were found to be 20% more likely to receive a CRC diagnosis, and are about 40% more likely to die from CRC, according to the American Cancer Society (ACS).

In this study, the researchers aimed to examine the relationship between ethnic group, route to diagnosis, early-onset CRC, and stage at diagnosis.¹

This study analyzed data for all individuals diagnosed with CRC in England between January 1, 2012, and December 31, 2017. Key variables included age at diagnosis, tumor stage, tumor site, socioeconomic status, Charlson Comorbidity Score, and ethnicity.

Participants were grouped into broad ethnic categories: Asian, Black, White, other, mixed and multiple, and unknown. Age at diagnosis was categorized into 4 groups: early onset (younger than 50 years), prescreening (aged 50-59 years), screening age (aged 60-74 years), and postscreening (aged 75 years and older). Routes to CRC diagnosis were classified into 6 pathways: emergency, general practitioner (GP) referral, other hospital (including inpatient and outpatient diagnoses), screening, 2-week wait (TWW) referral, and unknown (including death certificate only and other unspecified routes).

Researchers observed significant ethnic disparities in CRC diagnosis patterns. Early-onset CRC was least prevalent among White individuals (5.5%) compared with higher rates in the Asian (17.9%), Black (15.5%), and mixed and multiple ethnic groups (21.8%) (P < .01). Diagnosis through a TWW referral was notably less common among individuals from Asian (OR, 0.84; 95% CI, 0.79–0.91), Black (OR, 0.86; 95% CI, 0.79–0.93), other (OR, 0.8; 95% CI, 0.73–0.90), and unknown ethnic groups (OR, 0.70; 95% CI, 0.66–0.73) compared with the White group. Additionally, individuals from the Asian ethnic group had significantly lower odds of receiving an emergency diagnosis than their White counterparts (OR, 0.90; 95% CI, 0.83–0.97).

Adjusted analyses further showed that Asian individuals were less likely to be diagnosed at stage IV compared with White individuals (OR, 0.82; 95% CI, 0.76–0.88), emphasizing differences in diagnostic pathways and disease progression by ethnicity.

However, several limitations must be acknowledged. The study relied on retrospective, routinely collected health care data, which has known issues with the categorization of ethnicity. Additionally, the clustering of demographic factors such as age, socioeconomic status, and ethnicity made it challenging to disentangle their individual relationships with CRC diagnosis and outcomes.

Despite these limitations, the researchers believe the study provides insights that underscore the critical need for equitable CRC screening and diagnostic pathways to address ethnic disparities and improve outcomes.

“The differences in the tumor and demographics observed between the ethnic groups in this study demonstrate the need for careful consideration when designing CRC services to ensure that both interventions and education meet the needs of the target population,” wrote the researchers.

References

1. Birch RJ, Burr NE, Taylor JC, et al. Inequalities in colorectal cancer diagnosis by ethnic group: a population-level study in the English National Health Service. BMJ Open Gastroenterol. 2025;12(1):e001629. doi:10.1136/bmjgast-2024-001629

2. Werner C. Addressing racial disparities in colorectal cancer. Healthline. January 12, 2023. Accessed January 13, 2025. https://www.healthline.com/health/colorectal-cancer/racial-disparities-in-colorectal-cancer.