Risk of advanced colorectal neoplasia according to age and gender.

Colorectal cancer (CRC) is one of the leading causes of cancer related morbidity and death. Despite the fact that the mean age at diagnosis of CRC is lower in men, screening by colonoscopy or fecal occult blood test (FOBT) is initiated at same age in both genders. The prevalence of the common CRC precursor lesion, advanced adenoma, is well documented only in the screening population. The purpose of this study was to assess the risk of advanced adenoma at ages below screening age. We analyzed data from a census of 625,918 outpatient colonoscopies performed in adults in Bavaria between 2006 and 2008. A logistic regression model to determine gender- and age-specific risk of advanced neoplasia was developed. Advanced neoplasia was found in 16,740 women (4.6%) and 22,684 men (8.6%). Male sex was associated with an overall increased risk of advanced neoplasia (odds ratio 1.95; 95% confidence interval, CI, 1.91 to 2.00). At any age and in any indication group, more colonoscopies were needed in women than in men to detect advanced adenoma or cancer. At age 75 14.8 (95% CI, 14.4-15.2) screening, 18.2 (95% CI, 17.7-18.7) diagnostic, and 7.9 (95% CI, 7.6-8.2) colonoscopies to follow up on a positive FOBT (FOBT colonoscopies) were needed to find advanced adenoma in women. At age 50 39.0 (95% CI, 38.0-40.0) diagnostic, and 16.3 (95% CI, 15.7-16.9) FOBT colonoscopies were needed. Comparable numbers were reached 20 and 10 years earlier in men than in women, respectively. At any age and independent of the indication for colonoscopy, men are at higher risk of having advanced neoplasia diagnosed upon colonoscopy than women. This suggests that starting screening earlier in life in men than in women might result in a relevant increase in the detection of asymptomatic preneoplastic and neoplastic colonic lesions

A Direct Comparison of the Prevalence of Advanced Adenoma and Cancer between Surveillance and Screening Colonoscopies

Background/Aims: Surveillance colonoscopy is recommended afterpolypectomy of adenoma and surgery for colorectal cancer. The purpose ofthis study was to assess the frequency of advanced adenoma and cancer incolonoscopies performed for surveillance compared to screeningcolonoscopies. Methods: Analysis of relative frequencies of findings incolonoscopies performed for post-adenoma surveillance (post-ad),post-cancer surveillance (post-crc), screening, and follow-up of apositive fecal occult blood test (FOBT). Logistic regression was used toidentify the risk for advanced adenoma (adenoma mm, containinghigh-grade dysplasia, or villous histology) and cancer. Results: 324,912 colonoscopies were included in the analysis: 81,877 post-ad, 26,89 6post-crc, 178,305 screening, 37,834 positive FOBT. Advanced adenoma(cancer) was diagnosed in 8.0% (0.4%) of post-ad, 5.0% (1.0%) ofpost-crc, 7.4% (1.1%) of screening, and 11.7% (3.6%) of positiveFOBT colonoscopies. Compared to screening, the odds ratios for findingadvanced adenoma were 0.93 (95% CI 0.88-0.98) for post-ad, 0.96(0.86-1.08) for post-crc, and 1.18 (1.09-1.28) for positive FOBTcolonoscopies. The odds ratios for the diagnosis of cancer were 0.29(0.24-0.36) for post-ad, 0.81 (0.61-1.07) for post-crc, and 2.77(2.43-3.17) for positive FOBT. Conclusion: Colonoscopy for post-adsurveillance but not colonoscopy for post-crc surveillance is associatedwith a lower risk of diagnosis of advanced adenoma and cancer

A Direct Comparison of the Prevalence of Advanced Adenoma and Cancer between Surveillance and Screening Colonoscopies

Background/Aims: Surveillance colonoscopy is recommended afterpolypectomy of adenoma and surgery for colorectal cancer. The purpose ofthis study was to assess the frequency of advanced adenoma and cancer incolonoscopies performed for surveillance compared to screeningcolonoscopies. Methods: Analysis of relative frequencies of findings incolonoscopies performed for post-adenoma surveillance (post-ad),post-cancer surveillance (post-crc), screening, and follow-up of apositive fecal occult blood test (FOBT). Logistic regression was used toidentify the risk for advanced adenoma (adenoma mm, containinghigh-grade dysplasia, or villous histology) and cancer. Results: 324,912 colonoscopies were included in the analysis: 81,877 post-ad, 26,89 6post-crc, 178,305 screening, 37,834 positive FOBT. Advanced adenoma(cancer) was diagnosed in 8.0% (0.4%) of post-ad, 5.0% (1.0%) ofpost-crc, 7.4% (1.1%) of screening, and 11.7% (3.6%) of positiveFOBT colonoscopies. Compared to screening, the odds ratios for findingadvanced adenoma were 0.93 (95% CI 0.88-0.98) for post-ad, 0.96(0.86-1.08) for post-crc, and 1.18 (1.09-1.28) for positive FOBTcolonoscopies. The odds ratios for the diagnosis of cancer were 0.29(0.24-0.36) for post-ad, 0.81 (0.61-1.07) for post-crc, and 2.77(2.43-3.17) for positive FOBT. Conclusion: Colonoscopy for post-adsurveillance but not colonoscopy for post-crc surveillance is associatedwith a lower risk of diagnosis of advanced adenoma and cancer

Risk factors for advanced neoplasia within subcentimetric polyps: implications for diagnostic imaging

Objective: Diagnostic imaging by CT colonography and capsule endoscopy is used to detect colonic lesions. Controversy exists regarding the work-up of subcentimetric lesions. The aim of this study was to identify risk indicators for advanced neoplasia (AN) in subcentimetric polyps. Design: Colonoscopies were classified on the basis of the largest lesion found. AN was defined as high-grade dysplasia, villous histology, or cancer. Logistic regression models were developed to identify risk factors for AN, and validated on separate datasets. A risk index based on the logistic regression was generated, and the number needed to screen (NNS) to detect AN was determined. Results: 1 077 956 colonoscopies identified 106 270 intermediate (5-9 mm) and 198 954 diminutive (= 85 versus = 85 versus <45 years, 1.1 (95% CI 1.1 to 1.2) for male sex, 1.6 (95% CI 1.4 to 1.7) for occult blood, 1.3 (95% CI 1.2 to 1.5) for overt blood in stool, 1.3 (95% CI 1.2 to 1.4) for more than four lesions, and 2.2 (95% CI 2.1 to 2.3) for pedunculated versus sessile lesions. At median risk index values, the NNS was 9.3 (95% CI 9.1 to 9.5) in individuals with intermediate lesions and 29.4 (95% CI 28.5 to 30.2) in those with diminutive lesions. Compared with the NNS of 15 of the whole cohort, the majority of intermediate, but a minority of diminutive, lesions were deemed at high risk of AN. Conclusion: This study successfully identified risk factors and established a risk index for subcentimetric lesions. This has implications for the work-up of patients with subcentimetric lesions identified on diagnostic imaging