The Histologic and Colonoscopic Features and p53 Protein Overexpression of Serrated Adenoma

Kim, Sang Gyune; Lee, Moon Sung; Kim, Jin Oh; Cheon, Gab Jin; Jung, In Seop; Cheon, Young Koog; Cho, Joo Young; Lee, Joon Seong; Jin, So Young; Shim, Chan Sup

Abstract

BACKGROUND/AIMS: Serrated adenomas (SA) is a distinct form of colorectal neoplasia, in which adenomatous glands have a serrated epithelial arrangement observed in hyperplastic polyps. SA is defined as a neoplastic lesion composed of a monotonous cell population with atypical nuclei proliferating in a serrated glandular architecture. The aims were to clarify colonoscopic and histologic features, p53 protein overexpression of SA.
METHODS
One hundred and five SAs were obtained from 50 patients. We examined the location, size, colonoscopic findings, dysplasia, combined lesions. Twenty randomly selected cases of SA were compared with 24 cases of hyperplastic polyp and 21 cases of tubular adenoma for p53 protein overexpression.
RESULTS
Twenty-five patients (50%) had a single SA. The most common site was the sigmoid colon (30.5%). Out of 105 SAs, 83 (79%) were less than 5 mm in diameter. The endoscopic appearance showed that 52 cases of (49.5%) SAs were sessile type. The p53 protein overexpression was noted in none of hyperplastic polyps, in 55% of SAs (11/20), and in 76.2% of tubular adenomas.
CONCLUSIONS
According to this study, SAs are generally sessile type sized less than 5 mm and commonly observed in the sigmoid colon. Moreover, SAs show higher overexpression rate of p53 protein than hyperplastic polyps. Thus, the careful observation is required considering its malignant potential.