However, because of the paucity of studies and limitations of the study designs, questions have been raised about the reproducibility of the results, particularly for large polyps. With current techniques, MR colonography does not perform as well as CTC for detection of polyps, especially for small lesions. Fewer published studies are available evaluating MR colonography as compared to CTC, and sample sizes are generally small for MR colonography studies, which remains primarily an investigational technique. In a systematic review of 13 prospective studies evaluating MR colonography performance in 1,285 Colorectal Cancer Screening Variant 2: Colorectal cancer screening. Moderate-risk individual. First-degree family history of cancer or adenoma. Initial screening, then follow-up every 5 years after initial negative screen. CTC Less evidence is available assessing the performance of CTC in moderate-risk as compared to average-risk individuals. In a study evaluating 156 asymptomatic individuals with a family history of colorectal cancer (defined as a first-degree relative [parent, sibling, or child] diagnosed with colorectal cancer before 60 years of age, or 2 first-degree relatives diagnosed with colorectal cancer at any age) and 8,857 subjects without family history of colorectal cancer, the referral rate for colonoscopy was higher in the family history cohort (16.0% versus 10.5%; P=0.035), but the frequencies of proven cancer (0.0% versus 0.4%), advanced adenoma (4.5% versus 3.2%), and nonadvanced adenoma (5.1% versus 2.6%) were not significantly increased [78]. The results of this study suggest that CTC is a viable screening option for individuals at moderate risk due to family history. DCBE Limited evidence is available regarding the performance of DCBE in individuals with a family history of colorectal cancer.
Colorectal Cancer Screening. However, because of the paucity of studies and limitations of the study designs, questions have been raised about the reproducibility of the results, particularly for large polyps. With current techniques, MR colonography does not perform as well as CTC for detection of polyps, especially for small lesions. Fewer published studies are available evaluating MR colonography as compared to CTC, and sample sizes are generally small for MR colonography studies, which remains primarily an investigational technique. In a systematic review of 13 prospective studies evaluating MR colonography performance in 1,285 Colorectal Cancer Screening Variant 2: Colorectal cancer screening. Moderate-risk individual. First-degree family history of cancer or adenoma. Initial screening, then follow-up every 5 years after initial negative screen. CTC Less evidence is available assessing the performance of CTC in moderate-risk as compared to average-risk individuals. In a study evaluating 156 asymptomatic individuals with a family history of colorectal cancer (defined as a first-degree relative [parent, sibling, or child] diagnosed with colorectal cancer before 60 years of age, or 2 first-degree relatives diagnosed with colorectal cancer at any age) and 8,857 subjects without family history of colorectal cancer, the referral rate for colonoscopy was higher in the family history cohort (16.0% versus 10.5%; P=0.035), but the frequencies of proven cancer (0.0% versus 0.4%), advanced adenoma (4.5% versus 3.2%), and nonadvanced adenoma (5.1% versus 2.6%) were not significantly increased [78]. The results of this study suggest that CTC is a viable screening option for individuals at moderate risk due to family history. DCBE Limited evidence is available regarding the performance of DCBE in individuals with a family history of colorectal cancer.