Frequent beta-catenin nuclear labeling in sessile serrated polyps of the colorectum with neoplastic potential

• Published in: American journal of clinical pathology 2008-03, Vol.129 (3), p.416-423
• Main Authors: Wu, Julie M, Montgomery, Elizabeth A, Iacobuzio-Donahue, Christine A
• Format: Article
• Language: English
• Subjects: Adenoma - metabolism; Adenoma - pathology; beta Catenin - metabolism; Biomarkers, Tumor - analysis; CDX2 Transcription Factor; Cell Nucleus - metabolism; Colonic Polyps - metabolism; Colonic Polyps - pathology; Colorectal Neoplasms - metabolism; Colorectal Neoplasms - pathology; Female; Homeodomain Proteins - metabolism; Humans; Immunohistochemistry; Keratin-20 - metabolism; Keratin-7 - metabolism; Male; Middle Aged; Precancerous Conditions - metabolism; Precancerous Conditions - pathology; Tumor Suppressor Protein p53 - metabolism
• ISSN: 0002-9173; 1943-7722
• DOI: 10.1309/603UQKM7C2KELGJU

We obtained 22 sessile serrated adenomas (SSAs) and 19 hyperplastic polyps (HPs) and performed immunolabeling for cytokeratins (CKs) 7 and 20, CDX2, beta-catenin, and p53 to determine the role of these markers in aiding distinction of lesions with neoplastic potential. Patients with SSAs more frequently had a prior or coexistent tubular adenoma (P = .004) that was right-sided (P = .00001) and larger (P = .03). No difference in CK7, CK20, or p53 labeling was found after correction for colonic location. However, CDX2 labeling was significantly lower in SSAs (P = .02) and was predominantly confined to the crypt bases, whereas it was diffusely positive in HPs (P < .001). Surprisingly, aberrant nuclear labeling for beta-catenin was found in 9 (41%) of the SSAs but in none of the HPs (P < .002). We propose that beta-catenin and/or CDX2 immunolabeling may have diagnostic usefulness in the evaluation of serrated polyps. These findings also suggest that Wnt signaling has a role in SSA development.