After diagnosing a patient with tongue cancer, a doctor will need to determine what type of cancer it is, the grade of the tumour, and the stage of the cancer. Doctors often establish a preliminary disease stage based on physical exam as well as findings on imaging that help to identify the spread of disease. In patients who undergo surgery, a more well-defined disease stage is determined based on pathology after surgery. It is important to note that oral cancers can sometimes be difficult to diagnose. If a doctor is having a hard time determining what type of cancer it is, he or she might ask for a second opinion and send some pieces of the tumour off to a specialist in head and neck pathology who deals more frequently with these types of tumours.
The most common type of tongue cancer is squamous cell carcinoma. More than 90% of mouth cancers are squamous cell carcinoma. Squamous cell carcinoma is a cancer that starts from abnormal cells on the surface layer of the lips or the lining of the mouth. If the cancer is discovered at an early stage, before invading past the deepest layer of the mouth lining, then it is called carcinoma in situ and has a good prognosis when removed. Another subtype is called verrucous carcinoma. This sub-type usually has a slow growth pattern and is less likely to spread to lymph nodes in the neck or other parts of the body.
Less common types of tongue cancer
|Carcinoma in situ (also called severe dysplasia)||This cancer is an early stage of squamous cell carcinoma in which there are cancerous cells on the lining of the mouth but they have not invaded past the outermost layer of tissue.|
|Verrucous carcinoma||This is a type of squamous cell carcinoma that has a better prognosis because it is less likely to spread.|
|Salivary gland cancers||There are minor salivary glands located under the lining of the mouth. This is why cancers in this region can be glandular malignancies referred to as adenocarcinomas, including mucoepidermoid carcinomas, and adenoid cystic carcinomas.|
|Lymphoma||The mouth also has lymphoid cells under the surface. This is why lymphoma could in rare cases appear as a lump in the mouth.|
|Mucosal melanoma||These cancers come from skin cells (melanocytes). In rare cases, melanoma can be found in the lining of the mouth, nose and/or throat.|