Anatomy of the Larynx, or Voice Box
In order to begin to understand subglottic cancer, it helps to understand the anatomy of the larynx, or voice box. The larynx is located in the throat below the oropharynx and in front of the hypopharynx. It is in the middle of the neck, and is made up of multiple cartilaginous structures, the most prominent being the thyroid cartilage (sometimes called the Adam’s Apple).
The Supraglottis, Glottis & Subglottis
The anatomy of the larynx is quite complicated, but it can be broken down into three sections: the supraglottis, glottis, and subglottis. A cancer that starts in one part of the larynx can grow into one or both of the other subsites.
The Subglottis
The subglottis is part of the larynx that extends from the bottom of the true vocal cords downwards to the inferior border of the cricoid cartilage, where the larynx joins with the trachea, or windpipe.
The cricoid cartilage sits just below the thyroid cartilage and forms the inferior border of the larynx. The cricoid is the only complete cartilaginous ring of the airway. The membranous space between the thyroid and cricoid cartilage is called the cricothyroid membrane.
