Published online Jan 14, 2015. doi: 10.3748/wjg.v21.i2.525
Peer-review started: May 6, 2014
First decision: May 29, 2014
Revised: July 1, 2014
Accepted: August 28, 2014
Article in press: August 28, 2014
Published online: January 14, 2015
AIM: To investigate the relation of patient characteristics and procedural parameters to the endoscopic detection rate of colonic adenomas. Further to study, which factors may be capable to predict the localization of adenomatous lesions.
METHODS: We used the data base of a prospective randomized colonoscopy study (The ColoCap trial) to identify patients being diagnosed with colon adenoma. Logistic regression analysis was conducted to reveal predictors for adenoma detection in the entire colon and also with respect to the proximal and distal part. Covariates including age, gender, duration of colonoscopy and comorbidities were defined to determine association between predictors and adenoma detection.
RESULTS: Equal numbers of adenomas were detected in the proximal and distal side of the splenic flexure [126 (57%) vs 94 (43%), P = 0.104]. Simultaneous occurrence of adenomas in both sides of the colon was rare. The appearance of both proximal and distal adenoma was associated with increasing age (P = 0.008 and P = 0.024) and increasing duration of colonoscopy (P < 0.001 and P = 0.001). Male gender was a predictor for adenoma detection in the proximal colon (P = 0.008) but statistical significance was slightly missed with respect to the distal colon (P = 0.089). Alcohol abuse was found to be a predictor for the detection of distal adenoma (P = 0.041).
CONCLUSION: Increasing age and longer duration of colonoscopy are factors with a strong impact on adenoma detection both in the proximal and distal colon. Since proximal adenomas occurred in absence of distal adenomas, complete colonoscopy should be performed for screening.
Core tip: In this post-hoc study of a prospective randomized trial we analysed the impact of predefined patients and procedural characteristics on adenoma detection. Proximal lesions are at risk for being missed during colonoscopy but data is sparse regarding the existence of specific predictors for the detection of proximal and distal adenomas. Therefore, in our analysis we computed side specific regression analysis in order to define those predictors. Male gender, longer duration of colonoscopy procedure and increasing age were predictors for both proximal and distal adenomas. Proximal adenomas frequently occurred in the absence of distal adenomatous lesions. We therefore suggest total colonoscopy instead of sigmoidoscopy for colorectal cancer screening.