INTRODUCTION: An accumulation of genetic alterations forming the field of cancerization is an important event for the transformation from normal to cancer cell in multistep carcinogenesis. Histopathologically healthy tumor adjacent tissue might be considered as a cancerization field which is typified by genetic changes required for the development of cancer. Metallothionein (MT) is considered to be a protective and anti-apoptotic protein. The aim of our study was to evaluate the MT expression in head and neck squamous cells carcinoma and breast adenocarcinoma and their histologically healthy adjacent tissue.
MATERIALS AND METHODS: We have sampled 29 tissue samples in total derived from head and neck cancers and 29 samples of their clear surgical margins, 33 breast adenocarcinomas and 33 clear surgical margins. Antibody recognizing MT-1 was used for immunohistochemical analysis.
RESULTS: MT expression was revealed in 85,7% of head and neck cancers and 94% of breast adenocarcinomas. It was found in all tumor adjacent tissue. MT expression was statistically significantly higher in tumor adjacent tissue than in cancer tissue in cases with the presence of lymph node metastases in both, breast adenocarcinoma and head and neck squamous cell carcinoma. Generally stroma seems to respond to the presence of cancer by the expression of MT, even in tissues which normally do not express MT.
CONCLUSIONS: MT might be a normal or protective reaction of healthy adjacent tissue to the presence of tumor.