Predictors of advanced proximal neoplasia in persons with abnormal screening flexible sigmoidoscopy.
OBJECTIVE
The relationship between distal and proximal colonic findings is uncertain. Thus, there is no consensus on which findings on screening flexible sigmoidoscopy should trigger colonoscopy.


METHODS
We analyzed data from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial to assess the relationship between distal and proximal colonic findings.


RESULTS
A total of 8802 subjects had an abnormal baseline sigmoidoscopy and colonoscopy follow-up. Subjects with <10-mm single or multiple tubular adenomas had similar risks for advanced proximal neoplasia as subjects with hyperplastic polyps or other benign lesions (3%-5%). Subjects with large (>or=10 mm), villous, or severely dysplastic distal adenomas had similarly elevated risks for advanced proximal neoplasia (11%-12%). Multivariate logistic modeling showed a significantly increased risk for advanced proximal neoplasia associated with the presence of a large tubular (odds ratio [OR], 2.6; 95% confidence interval [CI], 2.0-3.4) or villous distal adenoma (OR, 2.7; 95% CI, 2.1-3.5) but not with the presence of one (OR, 1.05; 95% CI, 0.8-1.3) or multiple (OR, 0.8; 95% CI, 0.5-1.2) <10-mm tubular distal adenomas.


CONCLUSIONS
Among subjects with a polypoid lesion on screening flexible sigmoidoscopy, those with small tubular distal adenomas are at similar risk for advanced proximal neoplasia as those without distal adenomas. Subjects with a large, villous, or dysplastic distal adenoma are at increased risk. A strategy that encourages individuals with small tubular adenomas on sigmoidoscopy to undergo follow-up colonoscopy and excludes those with nonadenomatous lesions is of questionable validity, because both groups are at similar risk for advanced proximal neoplasia.
Pinsky
Paul F
PF
Division of Cancer Prevention, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892-7346, USA. pinskyp@mail.nih.gov
Schoen
Robert E
RE
Weissfeld
Joel L
JL
Bresalier
Robert S
RS
Hayes
Richard B
RB
Gohagan
John K
JK
D000236:Adenoma / Q000175:diagnosis*; D000465:Algorithms; D003110:Colonic Neoplasms / Q000175:diagnosis*; D003113:Colonoscopy; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015337:Multicenter Studies as Topic; D011446:Prospective Studies; D012372:ROC Curve; D016032:Randomized Controlled Trials as Topic; D012017:Referral and Consultation; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D012812:Sigmoidoscopy