Oral cancer or cancer of the mouth typically starts as a lesion that won’t go away. 95% of malignant or cancerous lesions are squamous cell carcinomas.
The most common site is the tongue, followed by the floor of the mouth, retromolar trigone (the area behind the wisdom teeth), tonsils and lower lip.
Other malignancies include salivary gland carcinoma, which could be ex pleomorphic adenoma (a malignant tumour that grows out of a benign tumour), adenoid cystic carcinoma (ACC) a tumour that grows out of the epithelial cells that line the salivary glands) and acinic cell carcinoma (a tumour that forms in mainly in the Parotid gland and that grows slowly). These cancers result in significant illness, and they affect physical appearance and function (i.e. swallowing, speaking and breathing).
In most countries, mortality ranges between 50-55% within five years. Lip cancers have the best rates of survival, at 90%, usually because it is diagnosed early. Prognosis is worse in older patients and slightly better in women.
Metastases occur less frequently compared to other cancers. However, squamous cell carcinoma spreads primarily to the lungs. The spine is the third most common site of metastasis after the lungs and liver.
 Trilling, Gregory M., et al. “Spinal metastasis in head and neck cancer.” Head & Neck Oncology, vol. 4, 2012, p. 36.