"The aerodigestive tract is a non-TA descriptive collective term for the respiratory tract and proximal portion of the digestive tract. As it is a non-standard term, its precise components vary somewhat with the context in which the term is being employed."
"Definitions of what precisely comprises the aerodigestive tract vary. In no small part, this is due to the context in which the term is being used. In the narrowest and a purely functional sense, it may be used to refer to those shared structures through which both air and food pass. This would therefore be the oral cavity and oropharynx only."
"The term upper aerodigestive tract is also often seen. This refers to the above structures excluding the oesophagus. It is a term commonly used with reference to upper aerodigestive tract malignancies. This usage stems from the fact that the mucosa of the upper aerodigestive tract is all lined with squamous cell epithelium, which may develop head and neck squamous cell carcinomas."