Squamous cell carcinoma (oral cavity)
Squamous cell carcinoma of the oral cavity is the most common (by far) of the malignant lesions affecting this region.
As they share epidemiology, pathology and general principles with other squamous cell carcinomas of the upper aerodigestive tract, those topics are covered there. Below are a few general comments specific to the oral cavity. Imaging findings, treatment, and prognosis are sometimes subsite-specific and are therefore in some cases discussed separately:
- squamous cell carcinoma of the tongue
- squamous cell carcinoma of the floor of mouth
- squamous cell carcinoma of the retromolar trigone
Epidemiology and risk factors are similar to squamous cell carcinomas elsewhere in the upper aerodigestive tract, with alcohol and tobacco use being the major risk factors. Human papillomavirus (HPV) infection is also associated with increased risk for oral cancer, but not as strongly as for oropharyngeal cancer . Though only accounting for a small subset of oral cancer, human papillomavirus infection is implicated in recent trends of increasing incidence of oral cancer in women younger than 40 years of age .
Over 75% of oral cavity squamous cell carcinomas occur in the lower lip, oral tongue, and floor of mouth .
A common staging system is used for all squamous cell carcinomas of the oral cavity, with tumor staging being based on size and extension into adjacent structures. Nodal staging is the same as that used for squamous cell carcinoma of the oral cavity, oropharynx, hypopharynx and larynx (see: staging of oral cavity squamous cell carcinomas).
The differential diagnosis of squamous cell carcinoma of the oral cavity is essentially that of other malignant lesions of the oral cavity as well as a few non-neoplastic lesions. It therefore includes:
- other malignancies
- minor salivary gland tumors
- adenoid cystic carcinoma
- mucoepidermoid carcinoma
- from teeth
- infected ranula
- radionecrosis of the mandible with associated soft tissue changes