African Americans should be screened at an earlier age for colorectal cancer

African Americans (AAs) have been shown to exhibit a higher incidence of colorectal cancer and experience lower survival compared with whites. There is disagreement regarding the age at which to initiate screening in AAs.

To calculate the age-specific incidence in AAs compared with whites while controlling for differences in socioeconomic status (SES) and to calculate the joinpoint at which the incidence begins to increase in each race.

Retrospective database review.

Surveillance, Epidemiology, and End Results database.

All patients with adenocarcinoma of the colon or rectum from 2000 through 2011 in the SEER 18 database.

We calculated the joinpoint of the upward trend of the age-adjusted incidence rate to determine the age at which the slope of the incidence curve began to increase in each race, while controlling for differences in SES by using a composite socioeconomic index.

Age-adjusted incidence of colon and rectal cancer.

The age-specific incidence of colorectal cancer (cases per 100,000 population) was 0.3 versus 0.4 in whites compared with AAs at 20 years of age. At 50 years of age, the incidence was 44.2 compared with 62.6 in whites compared with AAs. The model indicated a joinpoint at 47 years of age for whites (95% confidence interval, 45-49) and 43 for AAs (95% confidence interval, 42-45) (P < .001.) When SES was considered in stratification, joinpoints for whites were 48, 47, and 46 at high, middle, and low SES, respectively. Conversely, joinpoints of 43, 44, and 42 in the corresponding SES for AAs were noted (P ≤ .001).

There was no intervention, and we cannot conclude that changing screening policy would affect this disparity.

There is a disparity in the age-specific incidence of colorectal cancer in AAs compared with whites beginning at 45 years of age. These differences persist across socioeconomic strata.