Faculty Collaboration Database

Identification of histologically distinct conventional adenomas that arise predominately in patients with sessile serrated adenomas. Am J Surg Pathol 2010 Mar;34(3):355-63

Date

02/02/2010

Pubmed ID

20118768

DOI

10.1097/PAS.0b013e3181c6b9dd

Scopus ID

2-s2.0-77649199225 (requires institutional sign-in at Scopus site)   29 Citations

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.

Author List

Pai RK, Mackinnon AC, Joseph L, Noffsinger A, Hart J

MESH terms used to index this publication - Major topics in bold

Adenoma
Aged
Case-Control Studies
Colonic Neoplasms
Colonic Polyps
CpG Islands
DNA Methylation
DNA Mutational Analysis
Dilatation, Pathologic
Eosinophilia
Female
Gene Expression Regulation, Neoplastic
Humans
Hyperplasia
Immunohistochemistry
Intestinal Mucosa
Male
Middle Aged
Mucin-6
Mutation
Precancerous Conditions
Proto-Oncogene Proteins
Proto-Oncogene Proteins B-raf
Proto-Oncogene Proteins p21(ras)
ras Proteins