Reproducibility of the Villous Component and High-grade Dysplasia in Colorectal Adenomas <1 cm
ABSTRACT The presence of high-grade dysplasia (HGD) or villous component (VC) defines an advanced adenoma (AA) in patients with 1 or 2 adenomas <1 cm in size. Current consensus guidelines recommend that patients with AA undergo more intense postpolypectomy surveillance. In these clinical situations, the interobserver reliability in determining VC and HGD would play a major role in the credibility of these consensus guidelines. Therefore, the purpose of this study was to evaluate interobserver variability of VC and HGD in polyps <1 cm before and after the development of consensus criteria among gastrointestinal (GI) pathologists. Five GI pathologists independently evaluated 107 colorectal adenomas <1 cm, and classified them into tubular adenomas or adenomas with a VC (A-VC) and into low-grade dysplasia or HGD. Then a consensus conference was held and consensus criteria for VC and HGD were developed by group review. The same set of 107 slides were rereviewed independently by the same 5 GI pathologists. Interobserver variability using κ statistical analysis before and after the application of consensus criteria was assessed. A 1-sided z-test was used to determine whether κ scores increased after the consensus conference. Interobserver agreement before and after the consensus conference was poor for assessment of A-VC, HGD, and AA. These data calls into question the validity of basing clinical decisions on this distinction.
- Clinical gastroenterology and hepatology: the official clinical practice journal of the American Gastroenterological Association 01/2014; 12(1):3-6. DOI:10.1016/j.cgh.2013.10.005 · 6.53 Impact Factor
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ABSTRACT: Surveillance colonoscopy after endoscopic resection of colorectal adenomas is a crucial step in the concept of colorectal cancer screening. After identifying the patients at risk with screening and resection of adenomas, there has to be a tailored surveillance. Surveillance colonoscopy should detect recurrent and metachronal adenomas at a stage where they can be removed endoscopically. In the following, the criteria for a risk-adapted surveillance interval are presented. A literature review based on American, European, and German guidelines for surveillance after polypectomy and the German guideline for the diagnosis and treatment of ulcerative colitis, as well as a selective literature search into hereditary colorectal cancer were performed. State of the art surveillance after endoscopic resection of colorectal adenomas is based on a focused anamnesis and the index colonoscopy. On the basis of existing guidelines, a risk-adapted surveillance strategy can be implemented. Adherence to surveillance guidelines is a basic part of colorectal cancer screening and should be the starting point for further research.Viszeralmedizin / Visceral Medicine 02/2014; 30(1):2-2. DOI:10.1159/000357745 · 0.10 Impact Factor
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ABSTRACT: Aims Following the introduction of colorectal cancer screening programmes throughout Canada, it became necessary to standardise the diagnosis of colorectal adenomas. Canadian guidelines for standardised reporting of adenomas were developed in 2011. The aims of the present study were (a) to assess interobserver variability in the classification of dysplasia and architecture in adenomas and (b) to determine if interobserver variability could be improved by the adoption of criteria specified in the national guidelines. Methods An a priori power analysis was used to determine an adequate number of cases and participants. Twelve pathologists independently classified 40 whole-slide images of adenomas according to architecture and dysplasia grade. Following a wash-out period, participants were provided with the national guidelines and asked to reclassify the study set. Results At baseline, there was moderate interobserver agreement for architecture (K=0.4700; 95% CI 0.4427 to 0.4972) and dysplasia grade (K=0.5680; 95% CI 0.5299 to 0.6062). Following distribution of the guidelines, there was improved interobserver agreement in assessing architecture (K=0.5403; 95% CI 0.5133 to 0.5674)). For dysplasia grade, overall interobserver agreement remained moderate but decreased significantly (K=0.4833; 95% CI 0.4452 to 0.5215). Half of the cases contained high-grade dysplasia (HGD). Two pathologists diagnosed HGD in ≥75% of cases. Conclusions The improvement in interobserver agreement in classifying adenoma architecture suggests that national guidelines can be useful in disseminating knowledge, however, the variability in the diagnosis of HGD, even following guideline review suggests the need for ongoing knowledge-transfer exercises.Journal of Clinical Pathology 06/2014; 67(9). DOI:10.1136/jclinpath-2014-202177 · 2.55 Impact Factor