Progress of molecular targeted therapy for head and neck cancer in clinical aspects

Since the body's head and neck area affects many functions such as breathing, swallowing, and speaking, systemic treatments to head and neck cancer patients are important not only for survival but also for preserving functions and quality of life. With the progress that has been made in molecular targeted therapy, anti-EGFR antibody (cetuximab) and immune checkpoint inhibitors (nivolumab, pembrolizumab) have provided survival benefits to head and neck cancer patients and are approved for clinical practice. Clinical trials incorporating these new drugs for patients with locally advanced head/neck cancers are underway. However, the existing clinical evidence regarding molecular targeted drugs for head and neck cancers is based mostly on clinical trials allocated to squamous cell carcinoma patients. New targeted therapies for non-squamous cell carcinoma patients were recently reported, e.g., tyrosine kinase inhibitors for the treatment of thyroid cancers and HER2-targeted therapy for salivary gland cancers. With the goal of improving local control, molecular targeted treatment strategies as salvage local therapy are being investigated, including boron neutron capture therapy (BNCT) and near-infrared photoimmunotherapy (NIR-PIT). Herein the history and landscape of molecular targeted therapy for head and neck cancers are summarized and reviewed.