Node negative breast carcinoma: Hyperprolactinemia and/or overexpression of p53 as an independent predictor of poor prognosis compared to newer and established prognosticators

The purpose of this study was to investigate a prognostic indicator that can differentiate node negative breast cancer patients (N = 39, T2N0M0) with high risk and low risk for the development of recurrence or metastases. Preoperative plasma prolactin (PRL) was estimated by radioimmunoassay. The expression of PRL, p53, nm23, and c-erbB2 was investigated by immunohistochemical (IHC) localization; cathepsin D (CD, Enzyme Linked Sorbant Assay) and estrogen- and progesterone-receptors (ER and PR, Dextran coated charcoal method) were estimated in the tumor cytosols. The follow-up period was 2-6 years. Statistical comparisons were made between each marker for relapse-free survival (RFS) and overall survival (OS). Of the 39 patients, 18 had hyperprolactinemia (PRL > 20.0 ng/ml plasma), whereas overexpression of p53 was observed in 55% (17/31) tumors. These were independently and in combination associated with a reduced RFS and OS. The rest of the investigated markers did not show promising results. Hyperprolactinemia and/or overexpression of p53 were associated with aggressiveness of the tumor, early disease relapse or metastases, and poor OS in patients with node negative breast cancer. These two markers may enhance our ability to identify node negative breast cancer patients with aggressive tumors, for whom the use of adjuvant chemo and/or endocrine therapy is unequivocally justified.