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Although serrated polyps were historically considered to pose little risk, it is now understood that progression down the serrated pathway could account for as many as 15%-35% of colorectal cancers. The sessile serrated adenoma/polyp (SSA/P) is the most prevalent pre-invasive serrated lesion. Our objective was to identify the CpG loci that are persistently hyper-methylated during serrated carcinogenesis, from the early SSA/P lesion through the later cancer phases of neoplasia development. We queried the loci hyper-methylated in serrated cancers within our right-sided SSA/Ps from the New Hampshire Colonoscopy Registry, using the Illumina Infinium Human Methylation 450 k panel to comprehensively assess the DNA methylation status. We identified CpG loci and regions consistently hyper-methylated throughout the serrated carcinogenesis spectrum, in both our SSA/P specimens and in serrated cancers. Hyper-methylated CpG loci included the known the tumor suppressor gene RET (p = 5.72 x 10-10), as well as loci in differentially methylated regions for GSG1L, MIR4493, NTNG1, MCIDAS, ZNF568, and RERG. The hyper-methylated loci that we identified help characterize the biology of SSA/P development, and could be useful as therapeutic targets, or for future identification of patients who may benefit from shorter surveillance intervals. [ABSTRACT FROM AUTHOR]

Background & Aims: The adenoma detection rate (ADR) is an important quality indicator originally developed for screening colonoscopies. However, it is unclear whether the ADR should be calculated using data from screening and surveillance examinations. The recommended benchmark ADR for screening examinations is 20% (15% for women and 25% for men ≥50 y). There are few data available to compare ADRs from surveillance vs screening colonoscopies. We used a population-based registry to compare ADRs from screening vs surveillance colonoscopies. The serrated polyp detection rate (SDR), a potential new quality indicator, also was examined. Methods: By using data from the statewide New Hampshire Colonoscopy Registry, we excluded incomplete and diagnostic colonoscopies, and those performed in patients with inflammatory bowel disease, familial syndromes, or poor bowel preparation. We calculated the ADR and SDR (number of colonoscopies with at least 1 adenoma or serrated polyp detected, respectively, divided by the number of colonoscopies) from 9100 colonoscopies. The ADR and SDR were compared by colonoscopy indication (screening, surveillance), age at colonoscopy (50−64 y, ≥65 y), and sex. Results: The ADR was significantly higher in surveillance colonoscopies (37%) than screening colonoscopies (25%; P < .001). This difference was observed for both sexes and age groups. There was a smaller difference in the SDR of screening (8%) vs surveillance colonoscopies (10%; P < .001). Conclusions: In a population-based study, we found that addition of data from surveillance colonoscopies increased the ADR but had a smaller effect on the SDR. These findings indicate that when calculating ADR as a quality measure, endoscopists should use screening, rather than surveillance colonoscopy, data. [Copyright &y& Elsevier]

Background: Accuracy of familial risk assessment by endoscopists in determining colonoscopic screening and surveillance intervals is unknown.Aims: To investigate follow-up recommended by endoscopists for individuals at average or increased familial risk, following colonoscopies that were normal or yielded hyperplastic polyps only.Methods: Colonoscopy registry data was analyzed on 5,982 patients who had colonoscopy between 2004 and 2006. Patient information was linked with colonoscopy procedure information and pathology results. Patients with a personal or family history of colorectal cancer (CRC) or polyps, inflammatory bowel disease, or who had diagnostic, incomplete or suboptimally prepped examinations were excluded. The final analysis, which included 2,414 patients, investigated concordance of risk assessment between patient and endoscopist, and resulting endoscopist follow-up recommendations.Results: Following normal colonoscopy, 76% of average risk individuals were told to follow-up in 10 years, but if a hyperplastic polyp was found, less than 10 years was suggested for 76%. Many patients reporting a known familial cancer syndrome or a very strong family history did not have that history indicated on the endoscopist's procedure form, and recommended follow-up intervals were beyond guideline recommendations for 60.4% of the very high-risk group.Conclusions: Endoscopists may sometimes be unaware of the presence of familial risk factors, even for individuals at very high familial risk. Greater consistency and accuracy in familial risk assessments could significantly increase the efficacy of screening in preventing colorectal cancer. [ABSTRACT FROM AUTHOR]

Background: The need for colonoscopy in patients with adenomas 5 mm or less in diameter that are detected by sigmoidoscopy is controversial. Methods: We prospectively determined the prevalence of proximal colonic neoplasms in asymptomatic patients at average risk for colorectal cancer, each of whose index lesion on screening fiberoptic sigmoidoscopy was a benign adenoma. Polyps found on sigmoidoscopy underwent biopsy, and colonoscopy was recommended to all patients with neoplastic polyps. Rectosigmoid adenomas were classified as diminutive (<5 mm in diameter), small (6 to 10 mm in diameter), or large (>11 mm in diameter). Results: Of 3496 consecutive patients referred for sigmoidoscopy, 311 had neoplastic rectosigmoid polyps; 108 of these patients were excluded from the analysis because of a history of colonic neoplasia, symptoms, prior colonic evaluation, or incomplete follow-up data. The remaining 203 patients made up the study group, and all underwent colonoscopy. Neoplasms were found in the proximal colon in 40 of 137 patients (29 percent) with diminutive index polyps, 15 of 52 patients (29 percent) with small index polyps, and 8 of 14 patients (57 percent) with large index polyps. Advanced neoplasms (adenomas >10 mm in diameter, adenomas with a villous component or moderate-to-severe dysplasia, carcinoma in situ, or frank carcinoma) were found in 8 patients (6 percent), 5 patients (10 percent), and 4 patients (29 percent), respectively. Two patients with diminutive index polyps had proximal carcinoma in situ, and two had proximal stage I carcinomas; one patient with a large index polyp had proximal stage III carcinoma. Conclusions: The substantial prevalence of proximal colonic neoplasms, including advanced lesions, in asymptomatic average-risk patients with rectosigmoid adenomas <5 mm in diameter warrants colonoscopy in these patients. (N Engl J Med 1997;336:8-12.) [ABSTRACT FROM AUTHOR]