Wikibooks: Radiation Oncology/Head Neck/Nasopharynx/Overview

• Format: Book
• Language: English
• Subjects: Recess; Fossa; inuits
• Online Access: https://en.wikibooks.org/wiki/Radiation_Oncology/Head_%26_Neck/Nasopharynx/Overview

Radiation Oncology TOC Nasopharyngeal Cancer Overview =Epidemiology= Markedly different geographical prevalence Rare in the US 0.2 0.5 cases per 100 000 people Common in China Hong Kong and Taiwan 25 50 per 100 000. Accounts for ~5% of all cancers and ~50% of H N cancers in Taiwan Also common in North Africa the Middle East and in Inuits Association with salted fish Ebstein Barr virus Smoking and alcohol don t have a clear association with the disease In general affects a younger population Up to 90% present with N+ disease and ~50% have bilateral N+ disease =Clinical Presentation= Most commonly presents with a neck mass Refractory otitis media epixtaxis referred ear pain cranial neuropathy Most common cranial nerves affected are VI and V2 by tumor extension through foramen lacerum into cavernous sinus Syndromes Jacod s compression of CN II VI by extension into cavernous sinus leading to ophthalmoplegia blindness and trigeminal neuralgia Villaret compression of CN IX XII by parapharyngeal nodes leading to difficulty swallowing (IX) altered taste (IX) unilateral Horner s (X) paralysis of sternocleidomastoid/trapezius (XI) hemiglossal paralysis (XII) Vernet s syndrome (jugular foramen syndrome) compression of CN IX XI by extension into jugular foramen leading to difficulty swallowing vocal cord paralysis and paralysis of sternocleidomastoid/trapezius Trotter s triad (Sinus of Morgagni) unilateral conductive hearing loss (eustachian tube) impaired ipsilateral soft palate motility and mandibular pain =Anatomy= Includes vault lateral walls and posterior wall Anterior border begins at the end of the nasal cavity at the posterior choana (where nasal septum disappears). Radiographically this can be seen as the posterior wall of the maxillary sinus. It extends along plane of the airway to the level of free border of the soft palate posteriorly Lateral walls consist of the torus tubarius (Eustachian tube opening) pharyngeal recess (Fossa of Rosenmuller) posterior to torus tubarius and behind these are the superior ...