2016/10/01 by Victor Guharoy, Robert J Evans, Robert J. Evans +2
Medicine · #Gastric Cancer Management and Outcomes #Colorectal Cancer Screening and Detection
paper · doi:10.14309/00000434-201610001-00275
Introduction: Per 2012 AGA guidelines for colonoscopy surveillance, High-risk adenoma (HRA) refers to patients with tubular adenoma ≥ 10 mm, ≥ 3 adenomas, villous histology, or High Grade Dysplasia (HGD). It has been suggested in prior literature that diminutive polyps (defined as ≤ 5 mm in size) have a very low prevalence of advanced histology and evidence of invasive cancer. This has been referenced in the proposed “predict, resect, and discard” strategy, the principle value of which is reduction in cost for pathologic assessment of diminutive polyps. The purpose of this study was to determine the prevalence of HGD in diminutive polyps in a community-based setting and compare these findings with data published on diminutive polyps in the past 6 years. Methods: This study was a retrospective analysis of colonoscopies performed at a community-based endoscopy center from April 2015 to March 2016. Patient charts were reviewed for colonoscopy indication and polyp size based on colonoscopy report. A database system was used to query this information. A Pubmed search was used to identify studies since 2010 which had also looked at the prevalence of advanced adenomas in diminutive polyps. Results: 21 samples had initially been identified from April 2015-March 2016 as having HRA (all with HGD) in polyps < 10 mm based on pathology report review. After removal of patients who had larger polyps with evidence of HRA or malignancy at the same site, a remaining 7 samples had HGD in diminutive polyps. A database query identified size of polyps removed based on colonoscopy procedure reports. A total of 522 diminutive polyps were resected in 368 patients. 69% of these patients were between the ages of 45-75, and 15% were above the age of 75. Indications for colonoscopy were not limited to routine screening. The prevalence of HRA diminutive polyps in this population was determined to be 1.3%, which was consistent with findings from prior literature as outlined in Table 1.Table 1: Study Comparison of Prevalence of High Risk Adenoma in Diminutive PolypsConclusion: Prior studies looking at prevalence of HRA in small polyps (< 10 mm) have primarily been performed at Academic and Tertiary-Care Referral Centers. This study looked at the prevalence of HGD in diminutive polyps in a community-based setting. While our study indicates our findings are consistent with those of prior studies suggesting low prevalance of HGD in these polyps, the number is also not insignificant given diminutive polyps are estimated to be present in more than half the U.S. screening population.