Immunohistochemical detection of p53 protein expression in mammary carcinoma: a study of 80 cases.

Overexpression of p53 protein appears to be a common event in primary mammary carcinoma. This study was performed on 80 primary carcinomas of varying type and grade. Tumor p53 protein expression was detected by means of immunohistochemistry using the monoclonal antibody D07 on formalin fixed paraffin-embedded tissue sections. p53 overexpression was found in 50 (63%) of the 80 tumors. The correlation between p53 expression and high tumor grade, presence of in situ component and lymphocytic response was significant. However, no significant association was found between p53 expression and tumor size, age of the patients or tumor vascular invasion. Our study suggested that the immunohistochemical assay was a simple method of detection of mutant p53 proteins in routinely processed paraffin-embedded tissues of primary mammary carcinoma.