Abstract
Over the past years immuno-oncology has evolved and become a novel promising strategy for cancer therapy. Immune checkpoint inhibitors such as pembrolizumab or nivolumab, which target the interaction between programmed death receptor 1/programmed death ligand 1 (PD-1/PDL-1) and PDL-2, have been recently approved for the treatment of various malignancies and are currently being investigated in clinical phase III trials for head and neck squamous cell carcinoma (HNSCC). Data available from these trials indicate substantial activity accompanied by a favorable safety and toxicity profile in this patient population. This review article focuses on the molecular background, gives an overview of current clinical data of checkpoint inhibitors in HNSCC, and points out future challenges such as the need for appropriate biomarkers for these novel compounds.