The association between distal neoplasia on sigmoidoscopy and proximal colonic pathology on follow-up colonoscopy has been well-described.
However, it is not known if these findings are consistent across ethnic groups.
Dr Fritz Francois evaluated ethnic variations in the prevalence of proximal neoplasia on follow-up colonoscopy after a neoplastic lesion was found on sigmoidoscopy.
The research team prospectively enrolled 2207 asymptomatic patients at average-risk for colorectal
cancer referred for screening flexible sigmoidoscopy.
Colonoscopy was recommended for all patients with a polyp on flexible sigmoidoscopy, regardless of size.
Advanced neoplasms were defined as 10 mm or more in diameter or any adenoma, regardless of size, with villous histology, high-grade dysplasia, or cancer.
|Neoplasia occurred in 11% of African Americans, and 26% of Asians|
|American Journal of Gastroenterology|
The research team reported that 970 were Caucasian, 765 were African American, 395 were Hispanic, and 77 were Asian.
The prevalence of neoplasia in the distal colon was 13% in Caucasians, 11% in African Americans, 16% in Hispanics, and 25% in Asians.
Of the 290 patients with neoplastic lesions on sigmoidoscopy, follow-up colonoscopy identified neoplasms in the proximal colon in 67% of Hispanics.
The researchers found neoplasms in the proximal colon in 59% of African Americans, 64% of Caucasians, and 26% of Asians.
Advanced neoplasms in the proximal colon were highest in African Americans at 35 %, and lowest in Asians at 11 %.
Dr Francois's team concluded, “In our study population, Asians demonstrated a higher prevalence of distal colonic neoplasia, and a lower prevalence of proximal colonic neoplasia compared to non-Asians.”
“Future studies should explore ethnic variation in colonic neoplasia prevalence and location since ethnic variation could lead to tailored colorectal cancer screening strategies.”