Background and objectives:
Clear cell change of the large intestinal neoplasm is rare, and its character remains unclear. we report a case of the large intestinal adenoma with clear cell change with immunohistochemical and molecular studies to investigate whether the clear cell change is associated with a malignant progression of the adenoma.
Methods:
We studied the histochemical and immunohistochemical staining characteristics of the tumor by staining with hematoxylin-eosin, periodic acid-schiff, alcian blue, and by immunostaining using antibodies against carcinoembryonic antigen, epithelial membrane antigen, p53, and ki-67. the c-k-ras codon 12 point mutations were analyzed using a nonradioactive restriction fragment length polymorphism technique.
Results:
The tumor was composed of a typical tubular adenoma and a tubular adenoma with clear cytoplasm. the clear cytoplasm was negative by mucin stains. immunohistochemically p53 was negative in both the components. labeling index of ki-67 showed no significant difference between the two components. no codon 12 mutation of c-k-ras gene was observed in both the components.
Conclusion:
These findings suggest that the clear cell change of the tubular adenoma is not associated with a malignant progression in adenoma-carcinoma sequence involving c-k-ras and p53.