pyriform sinus
Pronunciation: PIE-ri-form
Lateral recess of hypopharynx; common site of hypopharyngeal cancer with tendency for submucosal spread.
Full Definition
The pyriform sinus is a paired, pear-shaped recess located in the lateral aspect of the hypopharynx, bounded medially by the aryepiglottic fold and laterally by the thyroid cartilage. This anatomical site is the most common location for hypopharyngeal cancer, accounting for approximately 65% of hypopharyngeal malignancies. Tumors arising in the pyriform sinus have a propensity for submucosal spread and early nodal metastasis due to the rich lymphatic drainage. The apex of the pyriform sinus extends inferiorly to the level of the vocal cords.
Usage
Usage note: Alternative spelling 'piriform sinus' is also acceptable in medical literature.
In Context
- "The tumor involved the left pyriform sinus with extension to the aryepiglottic fold." — Laryngoscopy report
- "Barium swallow demonstrated a filling defect in the right pyriform sinus." — Radiology report