BACKGROUND & AIMS: Sporadic colorectal cancers with a high degree of microsatellite instability are a clinically distinct subgroup with a high incidence of BRAF mutation and are widely considered to develop from serrated polyps. Previous studies of serrated polyps have been highly selected and largely retrospective. This prospective study examined the prevalence of sessile serrated adenomas and determined the incidence of BRAF and K-ras mutations in different types of polyps. METHODS: An unselected consecutive series of 190 patients underwent magnifying chromoendoscopy. Polyp location, size, and histologic classification were recorded. All polyps were screened for BRAF V600E and K-ras codon 12 and 13 mutations. RESULTS: Polyps were detected in 72% of patients. Most (60%) were adenomas (tubular adenomas, tubulovillous adenomas), followed by hyperplastic polyps (29%), sessile serrated adenomas (SSAs; 9%), traditional serrated adenomas (0.7%), and mixed polyps (1.7%). Adenomas were more prevalent in the proximal colon (73%), as were SSAs (75%), which tended to be large (64% >5 mm). The presence of at least one SSA was associated with increased polyp burden (5.0 vs 2.5; P < .0001) and female sex (P < .05). BRAF mutation was rare in adenomas (1/248 [0.4%]) but common in SSAs (78%), traditional serrated adenomas (66%), mixed polyps (57%), and microvesicular hyperplastic polyps (70%). K-ras mutations were significantly associated with goblet cell hyperplastic polyps and tubulovillous adenomas (P < .001). CONCLUSIONS: The prevalence of SSAs is approximately 9% in patients undergoing colonoscopy. They are associated with BRAF mutation, proximal location, female sex, and presence of multiple polyps. These findings emphasize the importance of identifying and removing these lesions for endoscopic prevention of colorectal cancer.
BACKGROUND & AIMS:Sporadic colorectal cancers with a high degree of microsatellite instability are a clinically distinct subgroup with a high incidence of BRAF mutation and are widely considered to develop from serrated polyps. Previous studies of serrated polyps have been highly selected and largely retrospective. This prospective study examined the prevalence of sessile serrated adenomas and determined the incidence of BRAF and K-ras mutations in different types of polyps. METHODS: An unselected consecutive series of 190 patients underwent magnifying chromoendoscopy. Polyp location, size, and histologic classification were recorded. All polyps were screened for BRAFV600E and K-ras codon 12 and 13 mutations. RESULTS:Polyps were detected in 72% of patients. Most (60%) were adenomas (tubular adenomas, tubulovillous adenomas), followed by hyperplastic polyps (29%), sessile serrated adenomas (SSAs; 9%), traditional serrated adenomas (0.7%), and mixed polyps (1.7%). Adenomas were more prevalent in the proximal colon (73%), as were SSAs (75%), which tended to be large (64% >5 mm). The presence of at least one SSA was associated with increased polyp burden (5.0 vs 2.5; P < .0001) and female sex (P < .05). BRAF mutation was rare in adenomas (1/248 [0.4%]) but common in SSAs (78%), traditional serrated adenomas (66%), mixed polyps (57%), and microvesicular hyperplastic polyps (70%). K-ras mutations were significantly associated with goblet cell hyperplastic polyps and tubulovillous adenomas (P < .001). CONCLUSIONS: The prevalence of SSAs is approximately 9% in patients undergoing colonoscopy. They are associated with BRAF mutation, proximal location, female sex, and presence of multiple polyps. These findings emphasize the importance of identifying and removing these lesions for endoscopic prevention of colorectal cancer.
Authors: Sara A Sajanti; Juha P Väyrynen; Päivi Sirniö; Kai Klintrup; Jyrki Mäkelä; Anne Tuomisto; Markus J Mäkinen Journal: Virchows Arch Date: 2014-11-14 Impact factor: 4.064
Authors: Alexandru V Olaru; Yulan Cheng; Rachana Agarwal; Jian Yang; Stefan David; John M Abraham; Wayne Yu; John H Kwon; Mark Lazarev; Steven R Brant; Michael R Marohn; David F Hutcheon; Noam Harpaz; Stephen J Meltzer; Yuriko Mori Journal: Inflamm Bowel Dis Date: 2011-08-09 Impact factor: 5.325
Authors: Xinwei Hua; Polly A Newcomb; Jessica Chubak; Rachel C Malen; Rebecca Ziebell; Aruna Kamineni; Lee-Ching Zhu; Melissa P Upton; Michelle A Wurscher; Sushma S Thomas; Hana Newman; Sheetal Hardikar; Andrea N Burnett-Hartman Journal: Cancer Causes Control Date: 2020-05-01 Impact factor: 2.506
Authors: Christian Hafner; Elena López-Knowles; Nuno M Luis; Agustí Toll; Eulàlia Baselga; Alex Fernández-Casado; Silvia Hernández; Adriana Ribé; Thomas Mentzel; Robert Stoehr; Ferdinand Hofstaedter; Michael Landthaler; Thomas Vogt; Ramòn M Pujol; Arndt Hartmann; Francisco X Real Journal: Proc Natl Acad Sci U S A Date: 2007-08-02 Impact factor: 11.205