Incidence of Serrated Lesion and Its Malignant Potential at Five Hospitals in Northern China
LP Wang, J Chen, HY Ning, XZ Zhang, J Chen, B Wang. General Hospital of Beijing Military Area, Dongcheng, Beijing, China; 252 PLA Hospital, Baoding, Hebei, China; Navy General Hospital, Haidian, Beijing, China; Julu County Hospital, Julu, Hebei, China; Dongzhimen Hospital, Dongcheng, Beijng, China
Background: There were more studies on molecular pathway and morphologic diagnostic criterion of serrated lesions. However, the incidence of serrated lesion in China has not been established yet with little knowledge on its malignant potential. The purpose of this study was to observe the incidence of serrated lesions in northern China and to compare the malignant potential of traditional serrated adenoma (TSA) with conventional adenoma(CAD).
Design: We retrospectively reviewed all the 5347 cases of colorectal polyps and adenoma from five hospital within last five years, All the serrated lesions were classified histologically, and other 187 cases of CAd(160 tubular adenoma and 27 villous adenoma) and 36 cases of invasive adenocarcinoma(ICA) were randomly selected as control from the General Hospital of Beijing Military Area. The degree of dysplasia and the expression of Ki-67, p53 andβ-Catenin were comparied between the TSA and CAD.
Results: Totally 5347 cases of colorectal polyps/adenomas were identified. Serrated lesions were found in 258 cases (4.82%), including 112 cases (2.09%) of hyperplastic polyps (HP) ,78 cases (1.57%) of TSA, 26 cases (0.48%) of sessile serrated adenoma (SSA). Sixty-two cases of TSA were identified from 3 hospitals, in which the moderate dysplasia was found in 13 cases, totally high-grade intraepithelial neoplasia and ICA were found in 6 cases (9.6%).Compared with 187 cases of CAD, the moderate dysplasia were found in 27 cases, totally high-grade intraepithelial neoplasia and ICA were found in 25 cases (13.3%) (χ2=19.373, P=0.000<0.05), and there were significant difference between TSA and CAD in degree of dysphasia. The expression of Ki-67, p53 andβ-Catenin had no significant difference between the TSA and CAD (p>0.05).
Conclusions: Incidence of serrated lesions is lower in northern China than that in Western countries. TSA has obvious malignant potential, but the rate with high-grade intraepithelial neoplasia and ICA is lower than that in the CAD.
Tuesday, March 23, 2010 9:30 AM
Poster Session III # 111, Tuesday Morning