Colon pathology detected after a positive screening flexible sigmoidoscopy: a prospective study in an ethnically diverse cohort.
OBJECTIVE
Although the association between distal neoplasia on sigmoidoscopy and proximal colonic pathology on follow-up colonoscopy has been well-described, it is not known if these findings are consistent across ethnic groups. The aim of this study was to evaluate ethnic variations in the prevalence of proximal neoplasia on follow-up colonoscopy after a neoplastic lesion is found on sigmoidoscopy.


METHODS
Consecutive asymptomatic patients at average-risk for colorectal cancer who were referred for screening flexible sigmoidoscopy were prospectively enrolled. Colonoscopy was recommended for all patients with a polyp on flexible sigmoidoscopy, regardless of size. Advanced neoplasms were defined as adenomas > or = 10 mm in diameter or any adenoma, regardless of size, with villous histology, high-grade dysplasia, or cancer.


RESULTS
Among the 2,207 patients who had sigmoidoscopy, 970 were Caucasian, 765 were African American, 395 were Hispanic, and 77 were Asian. The prevalence of neoplasia in the distal colon was 12.6% in Caucasians, 11.2% in African Americans, 15.9% in Hispanics, and 24.7% in Asians (p = 0.002). Of the 290 patients with neoplastic lesions on sigmoidoscopy, follow-up colonoscopy identified neoplasms in the proximal colon in 63.9% of Caucasians, 59.3% of African Americans, 66.7% of Hispanics, and 26.3% of Asians (p = 0.01). Advanced neoplasms in the proximal colon were highest in African Americans (34.9%) and lowest in Asians (10.5%).


CONCLUSIONS
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.
Department of Medicine and Division of Gastroenterology, VA New York Harbor Healthcare System and New York University School of Medicine, New York, New York 10010, USA.
Fritz
F
Francois
James
J
Park
Edmund J
EJ
Bini
D000368:Aged; D001213:Asian / Q000706:statistics & numerical data; D044383:Black People / Q000706:statistics & numerical data; D003106:Colon / Q000473:pathology; D003110:Colonic Neoplasms / Q000175:diagnosis* / Q000208:ethnology*; D003111:Colonic Polyps / Q000175:diagnosis / Q000208:ethnology / Q000473:pathology; D003113:Colonoscopy; D005260:Female; D006630:Hispanic or Latino / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012812:Sigmoidoscopy; D044465:White People / Q000706:statistics & numerical data; D001741:Black or African American