An overview of targeted treatments in cancer

BACKGROUND: The concept behind cancer treatment has evolved over the past decade from systemic, nonspecific, high-dose chemotherapy to targeted therapy and the introduction of cancer vaccines. Advanced technology and a better understanding of the cellular mechanisms that control cancer biology have helped in the development of such targeted treatment. OBJECTIVE: The aim of this article was to review some of the new and commonly used targeted treatments in cancer, emphasizing their mechanisms of action, safety profiles, and clinical applications. METHODS: The terms cancer, chemotherapy, monoclonal antibodies, targeted treatment, tyrosine kinase, epidermal growth factors, epidermal growth factor receptor, and cancer vaccines were used to search MEDLINE for English-language studies in humans, published between 1966 and March 2003. Identified publications addressing the objectives of this article were selected for review. RESULTS: All-trans-retinoic acid, imatinib, gemtuzumab ozogamicin, rituximab, alemtuzumab, trastuzumab, cetuximab, and gefitinib are recently developed cancer therapies that target specific types of cells and receptors. They have been used in a variety of hematologic and solid tumors, and their tolerability makes them attractive for use even in elderly and extensively pretreated patients. Vaccines using dendritic cells, tumor cells, and fusions of tumor cells and antigen-presenting cells have also shown some promise in research, but further study is needed to obtain better, sustained results. CONCLUSIONS: Targeted treatment and cancer vaccines are novel approaches in the treatment of cancer. Both fields are expanding rapidly, with new technology and ongoing medical research. The clinical implications of such agents, administered either solely or in combination with established chemotherapeutic agents, may ultimately lead to better regimens and improved clinical responses.