Microsatellite instability in hyperplastic and adenomatous polyps of the stomach

• Type: Article in International Scientific Journal
• Date: 1999

Authors

Nogueira, AMMF (Author) Other; Carneiro F (Author) FMUP; Seruca, R (Author) Other; Cirnes, L (Author) Other; Veiga, I (Author) Other; Machado JC (Author) Other; Sobrinho Simoes, M (Author) FMUP

Journal

Title: Cancer

Vol. 86

Pages: 1649-1656

ISSN: 0008-543X

Publisher: Wiley-Blackwell

Indexing

ISI Web of Knowledge - 32 Citations

Scopus - 41 Citations

Other information

Authenticus ID: P-001-2X2

DOI: 10.1002/(sici)1097-0142(19991101)86:9<1649::aid-cncr5>3.0.co;2-n

Abstract (EN): BACKGROUND. Few studies have focused on the presence and significance of microsatellite instability (MSI) in gastric polyps, and the results on record are conflicting. The aim of the current study was to address this issue, laking into consideration the 2 main types of gastric polyps, the coexistence of foci of malignant transformation, and the expression of p53 and ERBB-2. METHODS. Six hyperplastic polyps, 10 adenomatous polyps, and 4 adenomatous polyps displaying foci of malignant transformation (intestinal-type carcinoma) were studied for MSI. The authors analyzed a mononucleotide repeal microsatellite (BAT-26) and 5 dinucleotide repeats in microdissected formalin fixed, paraffin embedded tissue sections that were representative of the lesions. Expression of p53 and ERBB-2 were evaluated by immunohistochemistry. RESULTS. BAT-26 positivity was detected in 1 of 6 hyperplastic polyps (16.7%) and in 2 of 10 adenomas (20%) without malignant transformation. In the 4 adenomatous polyps with carcinomatous foci, BAT-26 positivity was detected in 2 cases (50%) in both (adenomatous and carcinomatous) components of the lesions. p53 immunoreactivity was observed in 6 adenomatous polyps, 2 of them with malignant transformation, Overexpression of the ERBB-2 protein was detected in 1 adenomatous polyp with malignant transformation. CONCLUSIONS. Replication error (RER+) phenotype occurs in both hyperplastic and adenomatous polyps of the stomach. The highest frequency is observed in adenomatous polyps with carcinomatous foci, suggesting that MSI may play a role in the process of malignant transformation in this setting. No significant association was observed between RER+ phenotype and overexpression of p53 or ERBB-2 proteins. (C) 1999 American Cancer Society.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 8