[Adjuvant systemic therapy of breast cancer--prognostic and predictive factors]

Adjuvant systemic treatment in breast cancer with Tamoxifen and/or chemotherapy has become a well-established standard of care during the last years. In adequately treated patients, a proportional reduction of the risk of recurrence of 20-35% can be achieved. Further improvement, however, is urgently needed, and new cytotoxic drugs (taxanes, vinorelbine, capecitabine), high dose chemotherapy in certain subgroups of patients, immunotherapy with monoclonal antibodies (herceptin), or gene therapeutic approaches might help to achieve that goal in the future. Another area of active research is the establishment of predictive factors, biological markers that would help to predict the benefit of a given therapy in an individual patient. This could help to improve the efficacy of a treatment in a population of patients likely to respond, while simultaneously sparing many patients with an unfavourable marker profile the toxic side effects of hormonal or cytotoxic therapy.