Multi-gene signatures in breast cancer: actual clinical impact
The molecular pathology has fundamentally modified our understanding of breast cancer. Today, breast cancer is understood as a heterogeneous disease consisting of at least five different subtypes. These subtypes show specific mRNA levels and somatic alterations and derive probably from different precursor cells. Multi-gene signatures enable us not only to differentiate these subtypes but also to define different risk groups for relapse after primary treatment. The clinical impact of these signatures is critically discussed in this review.