Development and Anatomy Embryology The oropharyngeal membrane divides the primitive oral cavity from the primitive pharynx. The oral cavity structures originating external to the oropharyngeal membrane are of ectodermal derivation; those arising internal to the oropharyngeal membrane are of endodermal…
Anatomic Relationships and Barriers or Pathways for Tumor Spread in the Hypopharynx and Larynx Hypopharynx The hypopharynx is in continuity with the oropharynx and extends from the level of the hyoid bone to the opening of the esophagus. It is…
Fibrous, Fibrohistiocytic, and Fibrovascular Lesions The great majority of soft-tissue masses of the mouth are hyperplastic inflammatory responses to local, usually chronic, trauma or infection. Moreover, these reactive lesions are much more common in the mouth than in other parts…
Anatomy and Histology Nasal Cavity The nose is a complex organ composed of two components: the external and the internal nose. The external nose is triangular, with a wide base covering two external openings, the nares or nostrils, separated by…
Introduction Squamous cell carcinoma (SCC) of the upper aerodigestive tract (UADT) is the most common malignant neoplasm of the mucosal lining of the upper food and air passages. The estimated worldwide global annual burden of 630,000 new patients diagnosed resulting…
General Introduction There is considerable literature on all aspects of precursor lesions for squamous cell carcinoma of the upper aerodigestive tract (UADT). Most data are specific to oral and laryngeal lesions. A common feature of all these precursor lesions, irrespective…