[Individualized treatment of breast cancer].

Breast cancer is the most frequent tumor in women. Clinical research over the last few years has resulted in an increasing differentiation of treatment strategies in the adjuvant setting as well as in metastatic breast cancer. In recent years, the medical treatment of breast cancer was complemented by agents with new mechanisms of action that depend on biological properties of the tumor. As these agents target tumor specific characteristics they are called targeted agents or targeted therapy. Most frequently, different receptors, key proteins of intracellular pathways, thyrosinkinases, or cytokines serve as tumor targets. Even in endocrine treatment relevant changes of practical guidelines emerged. The most important targeted therapies are reviewed with special regard to metastatic breast cancer.