Molecular Targeted Therapy in Prevalent Tumors: Learning from the Past and Future Perspectives

Important advances have been achieved with molecular targeted agents in clinical oncology. Breast, colon, and lung cancer, are now commonly treated with a combination of chemotherapy and targeted agents. In this article the authors discuss the limitations of targeted therapy development, failures of previous studies, and possible strategies for an intelligent drug development. Initial attempts to block mTOR in breast cancer, the magnitude of benefit obtained with anti-EGFR therapy in lung cancer, and the narrowing use of anti-EGFR therapy in colon cancer based on K-RAS status are discussed.