Lack of Prognostic Value of p53 Protein Expression in Node-Negative Breast Cancer

Abstract
Aims and background: The association of p53 protein accumulation and prognosis in node-negative breast cancer patients has been alternately demonstrated and denied in literature reports, and opinions on the use of p53 expression as an indicator of high risk of recurrence and as a guide for adjuvant therapy are controversial. Study design: The association of p53 protein accumulation with prognosis was retrospectively evaluated in a series of 221 node-negative breast cancer patients treated with surgery alone and followed up for a minimum of 10 years. p53 accumulation was determined by immunohistochemistry on archive material, and classified into four grades of increasing immunostaining. Results: No association was observed between p53 and age or pT category, whereas a significant association with nuclear grade was found (P = 0.0014). Univariate and multivariate analysis of 10-yr disease-free and overall survival showed a significant and independent prognostic association for tumor size (pT category) and nuclear grading but not for p53 expression, whatever grade grouping was used. Conclusions: We did not find any evidence supporting the use of p53 immunostaining in current practice as an independent prognostic indicator or as a discriminant factor for adjuvant treatment of node-negative breast cancer patients.