Kongressbericht vom 32. Annual San Antonio Breast Cancer Symposium vom 10.13.12.2009

The molecular basics of breast cancer and the resulting diagnostic and therapeutic opportunities dominated last year's annual San Antonio Breast Cancer meeting. Even though no breakthroughs in endocrine therapy were presented, the many facets of targeted therapies took center stage in the conference program. As in previous years, basic research, preclinical and clinical studies were presented. In the field of endocrine therapy the 5-year follow-up analysis of the TEAM trial demonstrated equal efficacy of exemestane upfront or as a sequential therapy after 2 years of tamoxifen. Moreover, a switch to exemestane was confirmed to be superior according to the DFS and for overall survival in the long-term follow-up of the IES study compared to 5 years of tamoxifen. The results of the MA 27 trial demonstrated the high prognostic impact of extended adjuvant therapy, especially in premenopausal woman (at the time of primary diagnosis). This effect remains constant even if therapy is initiated up to 6 years after primary adjuvant therapy. In metastatic breast cancer 500mg fulvestrant was found to provide a marginal prognostic benefit to women. A combination of fulvestrant and anastrozole just missed showing a higher efficacy than anastrozole monotherapy. With regard to bone health, priority was given to the prognostic impact of bisphosphonates and denosumab. The latter is a monoclonal antibody against RANK ligand and shows a superior efficacy to zoledronate in terms of pain relief and treatment of bone metastases. The value of adjuvant trastuzumab treatment was underlined by means of targeted therapies and concurrent treatment with taxane chemotherapy demonstrated the highest efficacy. In metastatic breast cancer a combination of trastuzumab and lapatinib was superior to monotherapy. Recent promising results of new EGF-receptor targeting drugs such as neratinib and T-DM1 confirmed the interesting data presented at an earlier meeting last year. In Her 2neu negative breast cancer, bevacizumab was demonstrated to be a good combination partner not only for taxanes but for capecitabine and gemcitabine as well. While some of the new multityrosine kinase inhibitors did not provide convincing results, others like sorafenib did demonstrate a good efficacy in combination with paclitaxel and capecitabine. All these tyrosine kinase inhibitors demand early and consequent prevention or treatment of associated side effects.