Immunohistochemical Study of p27Kip1 Expression in Gastric Adenomas and Early Gastric Carcinomas: Analysis of 65 Cases

Myong, Na Hye

Abstract

BACKGROUND: Recent studies have suggested that loss of p27Kip1 expression correlates with poor prognosis in gastric carcinomas, although the published data is still controversial. However, there are very few reports on the immunohistochemical expression of p27Kip1 in gastric adenomas and its significance in the progression of gastric adenomas to early gastric carcinomas (EGCs) is unclear. We therefore performed an immunohistochemical study for p27Kip1 expression in gastric adenomas with low- and high-grade dysplasia and EGCs to investigate the role of p27Kip1 expression in gastric carcinogenesis.
METHODS
We collected 45 cases of endoscopic mucosal resection specimens which were diagnosed as gastric adenomas and 20 cases of gastrectomy specimens showing EGCs. Using a monoclonal antibody against p27Kip1, the im- munohistochemistry was performed on paraffin-embedded specimens.
RESULTS
The loss of p27Kip1 immunoreactivity (<5% of the tumor cells) tended to be observed more frequently in high-grade adenomas than in the low-grade. The loss was found significantly higher in the EGCs than in both high-grade and low-grade adenomas (p=0.000). Gastric adenomas with villous component showed significant loss of p27Kip1 expression (p=0.057).
CONCLUSION
These results suggest that loss of p27Kip1 expression can play a role in the progression of gastric adenomas into adenocarcinomas and the villous component allows reliable estimation of the possibility for malignant transformation.