ABSTRACT
Head and neck squamous cell carcinoma (HNSCC) denotes a heterogeneous disease entity, which comprises a variety of tumors originating in the lip/oral cavity, hypopharynx, oropharynx, nasopharynx, or larynx with differences in epidemiology, etiology, and therapeutical approach. It is the sixth most common malignancy worldwide, accounting for approximately 6% of all cases, and is responsible for an estimated 1%–2% of all cancer deaths (Ferlay et al. 2010).
