Hispanic colorectal cancer prevalence low, but colon adenoma comparable

SAN DIEGO — Colorectal cancer prevalence was observed to be low among Hispanics, yet colon adenoma prevalence was found to be comparable to other ethnic and racial groups, according to data presented here at the 2012 Digestive Disease Week Annual Meeting.

Among the race-ethnic groups in the United States, African Americans represented the group with the highest colorectal cancer incidence and mortality, whereas Hispanics represented the lowest burden of the disease. To assess the prevalence of colorectal adenoma and carcinoma among the inner-city Hispanic population, researchers reviewed reports of 1,628 Hispanic patients who underwent colonoscopy at Howard University Hospital in Washington, D.C., from 2000 to 2010.

In this study, the researchers defined advanced adenoma as an adenoma of at least 1 cm in size or villous histology or high-grade dysplasia or invasive cancer.

“Our data showed low colorectal prevalence among Hispanics, yet colon adenoma prevalence was comparable to other ethnic and racial groups,” study researcher Hassan Ashktorab, PhD, associate professor in the department of medicine at the Howard University Cancer Center in Washington, D.C., told HemOnc Today. “Most colonic adenomas were located in the proximal colon, which supports the use of colonoscopy for colorectal screening.”

According to the results of the study, among all patients, adenoma prevalence was 16.5% (n=268), advanced adenoma was 2.3% (n=39) and colorectal cancer was 0.4% (n=7). Hyperplastic polyps were seen in 6.6% of the study cohort (n=107). Adenomas largely exhibited a proximal colonic distribution (53.7%; n=144), whereas hyperplastic polyps were most frequently located in the distal colon (70%; n=75). Among 11.7% (n=191) of patients who underwent screening colonoscopy, the prevalence of colorectal lesions was 21.4% for adenoma, 2.6% for advanced adenoma and 8.3% for hyperplastic polyps.

“Based on data from our screening colonoscopy program presented at Digestive Disease Week, the prevalence of adenomas, advanced adenomas and colorectal carcinomas is high in [African Americans] vs. other ethnic group in the US,” Ashktorab said. “This may explain the differences in the burden of colorectal cancer among African Americans compared to Hispanics and provides some evidence for earlier screening among African Americans.”

For more information:

Hassanzadeh H. #1780. Presented at: the 2012 Digestive Disease Week Annual Meeting; May 19-22, 2012; San Diego.

Disclosure: One of the study researchers reported a speaking and teaching position with Myriad Genetic Laboratories.