Endocrine Abstracts

Introduction: The mammary cancer is the most frequent malign tumor encountered in females, characterized by a high distant metastasis tendency. Among the potential prognosis factors, we mention the biomarkers that measure or are associated with biologic processes involved in the tumorous progression. The study analyzes the p53 protein’s positivity in correlation with the mammary cancer’s classical prognosis factors: the hystologic type, the histopathologic degree, the clinical stage and the status of the axial lymphonodules.

Purpose: The immunohistochemical evaluation (IHC) of an aggresivity marker in mammary cancer.

Methods: Using the immunohistochemical method of ABC Elite avidin–biotin complex staining and the p53 human anti-protein mouse monoclonal antibody, the DO 7 clone (1:500 dilution) on tissue sections fixed in 10% formaldehyde and included in paraffin, we have obtained a red staining of the tumorous cells’ nuclei.

Results: Out of 40 mammary carcinomas where we have immunohistochemically determined the p53 protein, we have assessed that 29 of them proved to be negative, 6 had a moderate staining and 5 had an intense staining. Several studies estimate that the over-expression of the p53 protein is comprised between 25 and 50% of the cases.

The p53 immunoreactivity was more frequently encountered in pre-menopausal women and in invaded axial lymphonodules tumors. We remarked a strong connection between the p53 over-expression and the studied tumors’ grading.

Conclusions: The results of the p53 staining present some variations, depending on the laboratories where the research has taken place (between 21.5 and 52% with different antibodies and on a different number of cases). In the studied cases, the percentage of p53 positive cells was of 27.5%. The p53 protein over-expression can be useful in establishing the mammary carcinomas prognosis, only if it is analyzed in connection with other factors, thus improving the information provided by them: therefore it contributes to the identification of the patients with an increased risk of disease progression.