Approximately 10-15% of head and neck cancers have a second primary diagnosed at the time of workup of the symptomatic primary site. Subclinical second primaries are most frequently diagnosed in the esophagus. Overall, 20-30% of head and neck patients develop a second primary at some point in their history. Tumors of minor salivary glands are assigned topography codes of the site in which they arise; for example, a tumor of a minor salivary gland of the floor of the mouth is coded to floor of mouth. The most common site for minor salivary gland tumors is the palate.
Tumors are malignant in 20-25% of parotid gland masses, 35-40% of submandibular gland, 50% of palate, and 95-100% of sublingual gland.
About 80% of paranasal sinus and nasal cavity tumors are squamous cell carcinoma; the remainder are adenocarcinomas. The maxillary sinuses develop squamous carcinoma, while the ethmoid sinuses tend to develop adenocarcinoma.
Oral cavity and pharynx cancers described as confined to mucosa should be reviewed with a pathologist to determine whether the tumor has penetrated the basement membrane, or whether it remains in situ.
None of the head and neck sites has a serosal surface. The muscularis propria forms the "wall" of the organ.
The gum and hard palate have neither a submucosa nor a muscularis propria, because they lie directly on bone. The equivalent structure to the submucosa for gum and hard palate is the mucoperiosteum.
If cervical nodes are reported as involved and laterality is not specified, assume nodes are ipsilateral.
In descriptions of cervical lymph nodes, the terms fixed and matted are to be considered as involvement of the nodes. The terms enlarged, palpable, lymphadenopathy, and shotty are not considered to be involvement.
A selective neck dissection will ordinarily include six or more lymph nodes. A radical or modified radical neck dissection will ordinarily include 10 or more lymph nodes.
If lymph nodes are described as matted and cannot be counted individually, the procedure that removed them should be coded as a lymph node dissection.
Wide excision performed within four months of excisional biopsy should be included when determining the code for site-specific surgery.
Use TX if the primary tumor was excised at another facility and no information about tumor size is available.
Do not add together the sizes of pieces of tumor removed at biopsy and at resection. Use the largest size of tumor, even if this is from the biopsy specimen. If no size is stated, record as 999 in the field "Size of Tumor."
The size of the primary tumor must be recorded in order to determine the T (tumor) classification of the TNM staging system: lip, buccal mucosa, alveolar ridge(s), retromolar trigone, floor of mouth, hard palate, oral tongue, anterior wall of oropharynx, vallecula, base of tongue, tonsil, tonsillar fossa, faucial pillars, posterior wall of oropharynx, soft palate, uvula, hypopharynx, pharyngo-esophageal junction (postcricoid area), pyriform sinus, posterior pharyngeal wall, major salivary glands, thyroid.
Various research and reporting agencies group anatomic sub sites of the head and neck in different ways for coding and staging purposes. The following variances are noted in SEER's Extent of Disease Coding Guidelines:
AJCC includes inferior surface of the soft palate (C05.1), base of tongue (C01.9) and uvula (C05.2) with oropharynx (C10._) for staging purposes.
AJCC includes lingual (anterior) surface of epiglottis (C10.1) with larynx (C32._).
Soft palate excludes nasopharyngeal (superior surface) of soft palate (C11.3).
The retromolar area (C06.2) is included with gum (C03._).
ICD-O code C06._ for buccal mucosa includes the membrane lining of the cheeks but not of the lips. AJCC includes labial mucosa with buccal mucosa.
Anatomic Limits of Oropharynx (from SEER Extent of Disease definitions)
Anterior Wall consists of the lingual (anterior) surface of the epiglottis and the pharyngoepiglottic and glossoepiglottic folds which bound the vallecula (the hollow formed at the junction of the base of the tongue and the epiglottis).
Lateral Walls include the tonsillar pillars, the tonsillar fossae, and the palatine (faucial) tonsils. On each side, the anterior pillar (glossopalatine fold) extends from the base of the tongue to the soft palate lying in front of the tonsillar fossa.
Posterior Wall extends from a level opposite the free borders of the soft palate to the tip of the epiglottis.
Anatomic Limits of Nasopharynx (from SEER Extent of Disease definitions)
Posterior Superior Wall extends from the choana, or the opening of the nasal cavities into the nasopharynx, posterior to a level opposite the soft palate. The pharyngeal tonsils (adenoids) are located in this part of the nasopharynx.
Lateral Walls extend from the base of the skull to the level of the soft palate and include Rosenmuller's fossa (pharyngeal recess).
Inferior Anterior Wall consists of the superior surface of the soft palate.
Anatomic Limits of Hyppharynx (from SEER Extent of Disease definitions)
Postcricoid Area (pharyngoesophageal junction) extends from the level of the arytenoid cartilages and connecting folds to the inferior border of the cricoid cartilage.
Pyriform Sinus extends from the pharyngoepiglottic fold to the upper edge of the esophagus. It is bounded laterally by the thyroid cartilage and medially by the hypopharyngeal surface of the aryepiglottic fold and the arytenoid and cricoid cartiages.
Posterior Hypopharyngeal Wall extends from the level of the tip of the epiglottis to the inferior margin of the cricoid cartilage and laterally to the posterior margins of the pyriform sinus.