Molecularly targeted therapies for breast cancer

Background: The management of patients with localized and advanced breast cancer continues to evolve. Chemotherapy, endocrine therapy, and trastuzumab are effective therapies but leave considerable room for improvement. As the cellular aberrations inherent to cancer cells in general and breast cancer cells specifically are better understood, therapies to target specific cellular pathways continue to be developed with the goal of expanding available effective therapy through better patient selection. Methods: We conducted a computerized search of the medical literature as well as a manual search of selected meeting abstracts. Results: Several targeted therapies are in phase III clinical trials testing their promise in the treatment of breast cancer. Many other agents are completing phase I and II testing. An overview of the most promising agents in clinical development is discussed herein. Conclusions: Targeted therapy for breast cancer is a reality at this time, and several new agents hold promise for expanding and refining the pool of patients likely to further benefit from this approach in the near future.