Head and neck cancer or throat cancer is a type of cancer which either beings in the lip, oral cavity (mouth), nasal cavity (inside the nose), paranasal sinuses, pharynx, and larynx. 90% of head and neck cancers are squamous cell carcinomas (SCCHN), originating from the mucosal lining (epithelium) of these regions. This cancer can be caused by drinking too much alcohol or chewing tobacco.