CANCER OF THE HYPOPHARYNX
ANATOMY. For the purposes of tumour classification the hypopharynx is
divided into three areas (Fig. 120).
1. The pyriform fossa is paired and lies on either side of the larynx being
bounded medially by the ary-epiglottic folds, laterally by the inner surface of
the thyroid ala, superiorly by the pharyngo-epiglottic fold and inferiorly it
extends to the mouth of the oesophagus. Like the ary-epiglottic fold which
bounds it, the pyriform fossa has a rich lymphatic drainage and a relatively
Fig. 120. The areas of the hypopharynx........pyriform fossa; «
posterior phaiyngeal wall.
• postcricoid region; •——••—
poor sensory supply resulting in tumours presenting late with lymph node
2. The posterior pharyngeal wall (Fig. 121) extends from the level of the hyoid
bone above to the level of the inferior margin of the cricoid cartilage below
and laterally to the posterior margins of the pyriform fossa.
3. The postcricoid region (Fig. 121) is in fact very small and is confined to the
posterior surface of the larynx and extends from the posterior surface of the
arytenoid cartilage and its connecting folds to the inferior surface of the
cricoid cartilage; its lateral margin is the posterior part of the pyriform fossa.
Inferior to the cricoid cartilage is the cervical oesophagus but, although
inaccurate, the name postcricoid has been applied to the whole area around
and including the mouth of the ossophagus. Postcricoid tumours per se are
very rare and in this book tumours of the cervical oesophagus (which may be
known as postcricoid) are dealt with in the chapter on dysphagia.