Predicting Outcome in Colonoscopic High-risk Surveillance

Abstract

Aim: Surveillance with colonoscopy in risk groups for colorectal cancer needs to be based on an adequate selection of individuals to examine and a well-devised timing. To stratify the risk of finding neoplasia at colonoscopy, a cohort with increased familial risk of colorectal cancer was studied.

Patients and methods: Based on family history, 1,203 individuals with at least two-fold increased risk of colorectal cancer were offered regular colonoscopies. The impact of different variables in the family history was assessed by logistic regression for the prevalence of adenoma and advanced adenoma. Findings at first colonoscopy were assessed regarding the association with risk of future lesions.

Results: The prevalence of advanced lesions, when controlling for age, was associated with the number of first-degree relatives with colorectal cancer, with an age below 50 years for the youngest family member with colorectal cancer, but not with gender. Family history had a low impact on the prevalence of simple adenoma. The risk of future advanced lesions was only associated with the prevalence of advanced lesions at the screening colonoscopy, whereas a finding of subsequent adenoma was associated with advanced lesions, adenomas and hyperplastic polyps.

Conclusion: Adenomas and advanced lesions were not associated with the same risk factors. In the present study, the most important risk factors for advanced lesions, including cancer, were the number of first-degree relatives and a young family member with colorectal cancer. Findings of simple adenomas and hyperplastic polyps did not seem to be associated with subsequent advanced lesions.

Keywords: Colorectal cancer; colonoscopy; family history; risk stratification; surveillance.