Tumors of the Pharynx

The naso-pharynx is the most superior part of the pharynx. It is a vault-shaped dome that acts as a conduit between the nasal cavity and the oro-pharynx for respiration. It is called the “blind spot” and is a common site for occult primary tumors. Approximately 80–85% of cancers are squamous cell carcinoma, and the remainder is primarily lymphoma, adenocarcinoma, and melanoma. The oro-pharynx is the middle part of the throat, which includes the base of the tongue, the tonsils, the soft palate, and the walls of the pharynx. Oropharyngeal cancer is rather uncommon and can be divided into two types, the one related to human papilloma virus (HPV) infection (HPV-positive cancer) and HPV-negative cancer, which is usually linked to alcohol or tobacco use. The hypopharynx is the region between the oropharynx above and the esophageal inlet below. Hypopharyngeal cancers are often named for their location, including pyriform sinus, lateral pharyngeal wall, posterior pharyngeal wall, or post-cricoid pharynx. The pyriform sinus is involved in 65–85% of cases, the posterior pharyngeal wall in 10–20%, and the post-cricoid area in 5–15%. This chapter discusses the etiology, pathology, clinical presentation, diagnosis, and management of tumors of the three regions of the pharynx.