Triple Negative Breast Cancer: Study of Molecular and Genetic Factors

Breast cancer triples negatives (TN; 15 % of the cases) are characterized by a high histoprognostic grade, a strong proliferation, a strong metastatic power, and a worse prognosis than the other forms of breast cancer. It is however a heterogenous group for histological and molecular level, but also for evolution. Most of the TN is part of the basal breast cancer subcategory. Until now, the medical treatment is based on chemotherapy.

Breast cancers by constitutional mutation of BRCA1 / BRCA2 (5 % of breast cancers) are mostly of basal type and their prognostic seems better that what could be expected from high grade tumours and without hormonal receptors. They would be much more frequent in the TN group. However, at this day, no prospective study was led to estimate this incidence, or to study the intervention of other genes of predisposition, as well to analyse the links between this phenotype and their consequences at the germinal or somatic level, in terms of associated molecular changes and prognosis.

The purpose of this study is, on a prospective study, to lead a joined analysis at the germinal level, in search of mutations of the main genes of breast cancer predisposition (BRCA1/2, PALB2, PTEN, PALB2), and at the tumour level (tissue micro-array and transcriptome), by correlating these results to the main clinical parameters.

The 5 years relapse-free survival will also be estimated.