Abstract
We have recently shown that a study population of patients with at least 1 sessile serrated adenoma (SSA) are 4 times more likely to harbor synchronous serrated polyps [SSAs, traditional serrated adenomas (TSAs) and right sided hyperplastic polyps] than a unselected population of patients. However, 35% of the polyps in the study patients were conventional adenomas (CAds). We hypothesized that the CAds in these study patients would have histologic and molecular differences compared with CAds from a control population without sessile serrated adenomas. To this end, 104 study and 79 control CAds were analyzed according to 9 histologic criteria. A subset of these polyps was also screened for BRAF mutations, KRAS mutations, CpG island methylation, and MUC6 expression. A total of 31 study CAds and 2 control CAds had atypical histologic features (bright cytoplasmic eosinophilia ± focal serrations and crypt dilatation). None of the adenomas tested had mutations in BRAF or KRAS. Evidence of low levels of CpG island methylation was seen in 35% of the atypical CAds and in only 4.5% of the typical CAds. In addition, these atypical CAds were more likely to express MUC6. Thus, the presence of cytoplasmic eosinophilia with or without focal serrations and crypt dilatation identifies a subset of CAds with characteristics of the serrated neoplasia pathway. These atypical CAds occur more commonly in patients predisposed to developing SSAs and suggest the presence of a mucosal field defect in these patients.
Original language | English (US) |
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Pages (from-to) | 355-363 |
Number of pages | 9 |
Journal | American Journal of Surgical Pathology |
Volume | 34 |
Issue number | 3 |
DOIs | |
State | Published - Mar 2010 |
Keywords
- CIMP
- Colorectal cancer
- Conventional adenoma
- CpG island methylation
- Hyperplastic polyp
- Hyperplastic polyposis syndrome
- Microsatellite instability
- Sessile serrated adenoma
- Sessile serrated polyp
- Traditional serrated adenoma
- Tubular adenoma
ASJC Scopus subject areas
- Anatomy
- Surgery
- Pathology and Forensic Medicine