Emerging therapies in the treatment of locally advanced squamous cell cancers of head and neck

Head and neck squamous cell cancers (HNSCCs) represent 4 to 5% of all solid malignancies. Despite improvements in diagnostic techniques, 60% of patients will present with locally advanced HNSCCs with a median survival of about 12 months and 5-year overall survival of approximately 10-40%. Recent clinical trials have altered the treatment landscape by refining existing forms of radiation, incorporation of IMRT, choice of chemotherapeutic agents, introduction of biological and targeted therapy, immunotherapy and gene therapy. Cetuximab, a monoclonal antibody directed against the human epidermal growth factor receptor (EGFR), has recently been approved in combination with RT in patients with locally advanced HNSCCs. Antiangiogenic therapies and tyrosine kinase inhibitors (gefitinib and erlotinib) have also shown promise in the clinical trials. Vandetanib, an antagonist of both vascular endothelial growth factor receptor (VEGFR) and the EGFR is currently being tested in phase II trial. New patents on hypoxia-inducible factor 1 alpha, mesenchymal-epithelial transition factor, insulin-like growth factor or the PI3K/AKT/mTOR pathway, farnesyl transferase inhibitors have shown promise in the management of HNSCCs. Nevertheless, identification of predictive biomarkers of resistance or sensitivity to these therapies remains a fundamental challenge in the optimal selection of patients most likely to benefit from them. However, increase in efficacy comes at the cost of increased toxicity. The current review focuses on insight into recent patents and updates on the clinical trials using new investigational agents in the management for HNSCCs.