[Serrated lesions of colon and their malignant potential].
OBJECTIVE
To study the serrated lesions of colon and to compare the malignant potential between traditional serrated adenomas (TSA) and conventional adenomas (CAD).


METHODS
A total of 5347 cases of colorectal polyps encountered in five regional hospitals during a five-year period were retrospectively reviewed. The serrated lesions were classified on the basis of histologic examination. One hundred and eighty-seven cases of CAD (including 160 cases of tubular adenoma and 27 cases of villous adenoma) and 36 cases of invasive adenocarcinoma were randomly selected as the controls. The degree of dysplasia and expressions of Ki-67, p53 and beta-catenin in TSA and CAD were compared.


RESULTS
Amongst the 5347 colorectal polyps studied, 258 cases (4.8%) of serrated lesions were found, which included 112 cases (43.4%, 112/258) of hyperplastic polyp, 78 cases (30.2%, 78/258) of TSA and 26 cases (10.1%, 26/258) of sessile serrated adenoma. Sixty-two cases of TSA were identified from 3 hospitals, in which moderate dysplasia was found in 13 cases. High-grade intraepithelial neoplasia and ICA were found in 6 cases (9.6%). Compared with the 187 cases of CAD, moderate dysplasia were found in 27 cases and high-grade intraepithelial neoplasia and invasive adenocarcinoma were found in 25 cases (13.3%, χ(2) = 19.373, P = 0.000). There was statistically significant difference between TSA and CAD in the degree of dysphasia. The expression of Ki-67, p53 and beta-catenin in TSA and CAD showed no significant difference (P > 0.05).


CONCLUSIONS
The incidence of serrated lesions is lower in northern Chinese population than that in Caucasians. TSA has obvious malignant potential; but the rate associated with high-grade intraepithelial neoplasia and invasive adenocarcinoma is lower than that in CAD.
Department of Pathology, General Hospital of Beijing Military Area, Beijing 100700, China. bzwlp@yahoo.com
Lu-ping
LP
Wang
Jian
J
Chen
Hao-yong
HY
Ning
Xin-zhong
XZ
Zhang
Juan
J
Cheng
Lin
L
Li
Bin
B
Wang
Xiao-juan
XJ
Dai
Hong-yan
HY
Zhu
Jin-hong
JH
Miao
Lin
L
Wang
D000230:Adenocarcinoma / Q000378:metabolism / Q000473:pathology; D000236:Adenoma / Q000145:classification / Q000378:metabolism / Q000473:pathology*; D018253:Adenoma, Villous / Q000145:classification / Q000378:metabolism / Q000473:pathology; D002471:Cell Transformation, Neoplastic / Q000473:pathology*; D003111:Colonic Polyps / Q000378:metabolism / Q000473:pathology; D015179:Colorectal Neoplasms / Q000145:classification / Q000378:metabolism / Q000473:pathology*; D006801:Humans; D007417:Intestinal Polyps / Q000378:metabolism / Q000473:pathology*; D019394:Ki-67 Antigen / Q000378:metabolism; D011230:Precancerous Conditions / Q000378:metabolism / Q000473:pathology; D012007:Rectum / Q000473:pathology; D012189:Retrospective Studies; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism; D051176:beta Catenin / Q000378:metabolism
D019394:Ki-67 Antigen; D016159:Tumor Suppressor Protein p53; D051176:beta Catenin