Identification of prognostic different subgroups in triple negative breast cancer by Her2-neu protein expression.

PURPOSE: Many patients with triple negative breast cancer (TNBC) have a poor outcome, but not all of them. This study has the aim to analyse the prognostic impact of tumour size, nodal status, grading, Her2-neu (human epithelial growth factor receptor 2) score and Ki-67 index. The main goal of this analysis is to find out if there are any differences in survival between patients with TNBC and a Her2-neu score 0 versus 1+2.

EXPERIMENTAL DESIGN: Retrospectively, we studied a cohort of 121 patients with TNBC, diagnosed at the Saarland University Medical Center between December 2004 and June 2013. We compared the disease-free survival (DFS) and overall survival (OS) in those women on the basis of the different Her2-neu scores (0 versus 1 or 2 with negative FISH).

RESULTS: One hundred and twenty one patients were included in this study. 58.68 % of them had a T2-4 tumour. 39.67 % were nodal positive and 67.77 % had high-grade tumours. The Her2-neu score was determined in 119 patients. 54.62 % of them had a score 0. In the 103 patients with a Ki-67 determination, the mean index was 44.5 %. We found that tumour size, nodal status and Her2-neu score are important prognostic factors. Patients with a Her2-neu score 0 had a significantly poorer outcome regarding DFS and OS. In contrast, the expression level of Ki-67 and the grading do not seem to have any prognostic value in TNBC.

CONCLUSION: Besides tumour stage, grading and nodal status, the Her2-neu score 0 is able to function as a prognostic factor in patients with TNBC.