Abstract
Metallothionein (MT) is a metal-binding protein with a low molecular weight (6000-7500), and is implicated in abnormal cell growth in some cancers. In the present study, the relationship between MT expression and the clinical features in oral squamous cell carcinomas was investigated. In 12 recurrent cases of oral cancer, the expression of MT was examined immunohistochemically in formalin-fixed, paraffin-embedded tissue sections using the avidinbiotin peroxidase complex method.
The percentages of MT positive cells in tissue sections from nonrecurrent cases (n=21), and recurrent cases (n=12) were 40.8% and 70.1%, respectively. Between these values, a significant difference was recognized.
Furthermore, in recurrent cases, the percentage of MT positive cells was 70.1% for primary cases (n=12), and 76.7% for recurrent cases (n=9) . Between these values, no significant difference was recognized. However, among 9 recurrent cases, 6 patients with increasing MT percentages died, whereas 3 patients with decreasing MT percentages survived.
In summary, immunohistochemical examination of MT in the primary lesion and recurrent lesion of tumors is useful for understanding the biological degree of malignancy of oral squamous cell carcinomas in clinical practice, and may be useful for selecting future treatment and evaluating the patients prognosis.
