The oral cavity (mouth): the lips, the tongue, the teeth, the gums, the lining inside the lips and cheeks, the floor of the mouth (under the tongue), the roof of the mouth, and the small area behind the wisdom teeth are all included in the oral cavity.
The oropharynx: includes the back one-third of the tongue, the back of the throat, and the tonsils.
Nasopharynx: includes the area behind the nose.
Hypopharynx: the lower part of the throat.
The larynx (voice box, located in front of the neck in the region of the Adam's apple): in the larynx, the cancer can occur in any of the three regions—the glottis (where the vocal cords are); the supraglottis (the area above the glottis), and the subglottis (the area that connects the glottis to the windpipe).
The most frequently occurring cancers of the head and neck area are oral cancers and laryngeal cancers. Almost half of all the head and neck cancers occur in the oral cavity, and a third are found in the larynx. By definition, the term "head and neck cancers" usually excludes tumors that occur in the brain.
Crystal Heather Kaczkowski, MSc., The Gale Group Inc., Gale, Detroit,