Role of colonoscopy and polyp characteristics in colorectal cancer after colonoscopic polyp detection: a population-based case-control study.
BACKGROUND
Studies have identified characteristics of adenomas detected on colonoscopy to be predictive of adenoma recurrence.


OBJECTIVE
To assess the role of both colonoscopy-related factors and polyp characteristics on the risk for colorectal cancer after colonoscopic polyp detection.


METHODS
Population-based case-control study (3148 case participants and 3274 control participants).


METHODS
Rhine-Neckar region of Germany.


METHODS
Case and control participants with physician-validated detection of polyps (other than hyperplastic polyps) at a previous colonoscopy in the past 10 years.


METHODS
Detailed history and results of previous colonoscopies were obtained through interviews and medical records. Case and control participants were compared according to colonoscopy-related factors (incompleteness, poor bowel preparation, incomplete removal of all polyps, and no surveillance colonoscopy within 5 years) and polyp characteristics (≥ 1 cm, villous components or high-grade dysplasia, ≥ 3 polyps, and ≥ 1 proximal polyp). Odds ratios (ORs) and attributable fractions were derived by using multiple logistic regression and the Levin formula.


RESULTS
155 case participants and 260 control participants with physician-validated polyp detection in the past 10 years were identified. The following characteristics were significantly more common among case participants than among control participants: not all polyps completely removed (29.0% vs. 9.6%; OR, 3.73 [95% CI, 2.11 to 6.60]), no surveillance colonoscopy within 5 years (26.5% vs. 11.5%; OR, 2.96 [CI, 1.70 to 5.16]), and detection of 3 or more polyps (14.2% vs. 7.3%; OR, 2.21 [CI, 1.07 to 4.54]). Odds ratios ranged from 1.12 to 1.42 and CIs included 1.00 for all other variables. Overall, 41.1% and 21.7% of cancer cases were statistically attributable to colonoscopy-related factors and polyp characteristics, respectively.


CONCLUSIONS
This was an observational study with potential for residual confounding and selection bias.


CONCLUSIONS
Colonoscopy-related factors are more important than polyp characteristics for stratification of colorectal cancer risk after colonoscopic polyp detection in the community setting.
Division of Clinical Epidemiology and Aging Research, German Cancer Research Center, Im Neuenheimer Feld 280, D-69120 Heidelberg, Germany. h.brenner@dkfz.de
Hermann
H
Brenner
Jenny
J
Chang-Claude
Lina
L
Jansen
Christoph M
CM
Seiler
Michael
M
Hoffmeister
D000236:Adenoma / Q000473:pathology* / Q000601:surgery*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D003111:Colonic Polyps / Q000473:pathology* / Q000601:surgery*; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000175:diagnosis*; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D010349:Patient Compliance; D012307:Risk Factors; D016896:Treatment Outcome