Oropharyngeal squamous cell carcinomas originate in the soft palate, tonsils, base of tongue, pharyngeal wall, or the vallecula, the fold located between the base of tongue and the epiglottis (figure 1) . Oropharyngeal cancer is a relatively uncommon malignancy, with approximately 123,000 cases of oropharyngeal and hypopharyngeal cancer diagnosed worldwide each year, which cause about 79,000 deaths .
The tumor node metastasis (TNM) staging system of the American Joint Committee on Cancer (AJCC) and the International Union for Cancer Control (UICC) is used to stage oropharyngeal cancer (table 1 and figure 2) . (See "Overview of the diagnosis and staging of head and neck cancer".)
The treatment of locally advanced, stage III to IVB (table 1) cancers of the oropharynx will be reviewed here. The treatment of early stage oropharyngeal cancer is discussed separately, as is the management of patients with distant metastases (stage IVC).
●(See "Treatment of early (stage I and II) head and neck cancer: The oropharynx", section on 'General principles'.)
●(See "Treatment of metastatic and recurrent head and neck cancer".)