• N J Carr, H Mahajan, K L Tan, N J Hawkins, and R L Ward.
• Graduate School of Medicine, University of Wollongong, New South Wales, Australia. ncarr@uow.edu.au
• J. Clin. Pathol. 2009 Jun 1; 62 (6): 516-8.

AimsTo determine the prevalence of colorectal polyps of different types in an unselected population, and to correlate the morphological diagnoses with BRAF mutation analysis.MethodsCases of colorectal polyps diagnosed at endoscopy were retrieved from the files of Southern.IML Pathology. All slides were reviewed and the lesions classified histologically. A diagnosis of sessile serrated adenoma was made even if the characteristic features were present only focally. If there was more than one polyp of a particular type in any patient, one lesion was chosen at random so that the results represent the number of patients with each type of polyp rather than the total number of polyps. A proportion of the polyps was subjected to BRAF mutation analysis.ResultsA total of 1479 patients were identified. Non-serrated ("conventional") adenomas were found in 964 patients (65%), hyperplastic polyps in 437 (30%), sessile serrated adenomas in 57 (3.9%), traditional serrated adenomas in 11 (0.7%) and mixed hyperplastic adenomatous polyps in 10 (0.7%). BRAF V600E mutation analysis was performed in 148 selected cases; mutations were found in 44/49 (90%) of lesions diagnosed as sessile serrated adenoma, in 10/34 (29%) of hyperplastic polyps of microvesicular type, in 4/11 (36%) of traditional serrated adenomas, in 10/10 (100%) of mixed hyperplastic adenomatous polyps, and in 2/42 (5%) of "conventional" adenomas.ConclusionsSessile serrated adenomas are encountered commonly in routine endoscopy practice. The histological diagnosis correlates strongly with the presence of BRAF mutation.

28 keywords...

hide…