[Gene expression profiles for therapeutic decisions in breast cancer]

In the early stages of breast cancer, surgery and radiotherapy arrest the local and regional disease. However 30% of patients will die as a consequence of tumor dissemination. Parameters with a relative predictive value are used to assess candidates to adjuvant therapy. Genomic analysis methods (cDNA microarray) identified a gene expression profile of greater aggressiveness in breast cancer. This knowledge generated the project "Translating Molecular Knowledge Into Early Breast Cancer Management" of the Breast International Group (BIG). This is a consortium of 32 research groups in which Chile participates through the Chilean Cooperative Oncological Research Group (GOCCHI). The project consists in three protocols. In the first, denominated MINDACT (Microarray for Node Negative Disease may Avoid Chemotherapy), 8000 women will be evaluated by gene expression profile and clinical pathological criteria to decide adjuvant therapy. Since a group of patients will not receive therapy, solely based on gene expression profile, GOCCHI is preparing a follow up protocol based on the expression of 22 genes. MINDACT is the first prospective effort to evaluate gene expression profiles in clinical practice. Our participation in this protocol, installs us in the first line of worldwide oncological investigation.