Prognostic value of a proliferation index including MIB1 and argyrophilic nucleolar organizer regions proteins in node-negative breast cancer.

Abstract

This study was designed to evaluate a cell proliferation marker, including the percentage of cycling cells (MIB1), and the duration of the cell cycle (assessed by argyrophilic nucleolar organizer regions proteins [AgNORs] measurement). We included 90 patients with invasive node-negative breast cancer. None received chemotherapy. With the help of a double-staining technique, a proliferation index (PI) was determined by multiplying the percentage of MIB1-positive cells by the mean area of the AgNORs present in those MIB1-positive cells. PI was evaluated for its impact on overall survival (OS) and disease-free survival (DFS). We demonstrated that PI was correlated to OS. For DFS, it conserved its high prognostic value only in univariate analysis. The global amount of AgNORs was more discriminative for DFS. PI and AgNOR quantification supplied additional prognosis information in node-negative patients, and we propose to integrate them in further studies.