Head & Neck

Oral Cancer

Oral cancer can develop in any part of the mouth, including the lips, gums, roof and floor of the mouth, tongue, and the inside lining of the cheeks and lips (see figure below). Tumors that grow in the mouth can be benign (noncancerous) or malignant (cancerous), or they can start out benign and later develop into cancer. Most cancers that develop in the mouth form in squamous cells, the thin cells that line the mouth and throat.

Diagnosing oral cancer

Symptoms that may point to oral cancer include a white or red patch on the gums, the tongue or the lining of the mouth; a swelling of the jaw that causes dentures to fit poorly or become uncomfortable; and unusual bleeding or pain in the mouth. However, these symptoms often are not a clear signal that something is wrong, which sometimes makes it difficult to diagnose oral cancer at an early stage. As a result, oral cancer has the opportunity to metastasize (spread) to nearby lymph nodes or other parts of the body before the cancer is diagnosed.

If your doctor suspects oral cancer, one or more of the following tests may be ordered:

  • Imaging tests, which allow your doctor to see the inside of the body. These tests are not used to diagnose oral cancers but can be used to look for a tumor or cancer spread, which helps your doctor stage your cancer. Imaging tests may include the following:
    • Computed tomography (CT) is a test that involves a scanner linked to a computer that makes a series of detailed cross-sectional images, taken from different angles, of areas inside the body. A dye may be injected into a vein or swallowed to help organs or tissues show up more clearly.
    • Magnetic resonance imaging (MRI) is a procedure that uses radio waves and a powerful magnet linked to a computer to create images, usually in 3D, of the tissues and organs inside your body.
    • Mouth and chest X-rays are images made with high-energy beams to look for abnormalities.
    • Positron emission tomography (PET) is a test to evaluate the function of the organs in the body. A sugar substance with a very low level of radioactivity is injected into the bloodstream through a vein in the arm. Cancer cells absorb large amounts of the sugar, so the radioactive sugar will gather in cancer cells. The PET scanner will produce images with bright spots that correspond to areas where there is a high concentration of radioactive sugar.
  • Endoscopy is a procedure in which the doctor uses a thin, lighted tube (endoscope) to check your throat.


Once oral cancer has been diagnosed, your doctor needs to stage the disease to determine the extent of your cancer, where it is located, and whether it has metastasized (spread) to nearby organs or tissue or to other parts of your body. Your physical exam, diagnostic tests and a pathology report help your doctor decide the stage of your cancer and develop a treatment plan.

The TNM staging system, developed by the American Joint Committee on Cancer (AJCC), is typically used to stage head and neck cancers. This system classifies the cancer by tumor (T), node (N) and metastasis (M). The T category describes the size and location of the primary tumor. The N category describes lymph node involvement, indicating whether the lymph nodes show evidence of cancer cells. The location of these lymph nodes is important because it shows how far the disease has spread. The pathologic N category (sometimes denoted as pN) describes how many lymph nodes are involved and the amount of tumor cells found in the nodes. The M category describes distant metastasis (spread of cancer to another part of the body), if any. Staging for the M category is mainly clinical; however, a new M subcategory may be given based on the presence of tumor cells that can only be detected using a microscope or molecular testing.

Once the cancer has been classified, an overall stage is assigned. The main stages are Stage 0 (or I) through Stage IV, where Stage 0 (also known as “in situ”) is a precursor of an invasive cancer. Stages I and II are confined to the local area where the cancer is found; Stage III has often spread to the regional lymph nodes or lymphatic channels; and Stage IV has spread to distant sites (such as the lung or bone). Even these basic stages are sometimes further divided into subgroups of tumors that have a similar prognosis (Stage IB, Stage IIIC, etc). This grouping allows doctors to more accurately predict survival outcome according to stage and to adjust the treatment to the stage or substage of the cancer. For certain cancers, the AJCC also recommends tumor genetic testing, which can help determine which treatments are likely to be most effective.

Although the original stage at diagnosis does not change, a doctor may reassess an individual’s cancer after treatment or if it has recurred, in a process known as restaging. This is rarely done but will likely involve the same diagnostic tests used for the original diagnosis. If a new stage is assigned, it’s often preceded by an “r” to denote that it’s a restage and different from the original stage given at diagnosis.

TNM classification for oral cancer

Classification Definition
Tumor (T)
Tx Primary tumor cannot be assessed.
T0 No evidence of primary tumor.
Tis Carcinoma in situ (cancer cells are present only in the surface layer of the throat but have not invaded into deeper layers).
T1 Tumor is 2 centimeters (cm) (about ¾ inch) or less in diameter.
T2 Tumor is more than 2 cm but not more than 4 cm in diameter.
T3 Tumor is more than 4 cm in diameter.
T4a Moderately advanced local disease. (lip) Tumor invades through cortical bone, inferior alveolar nerve, floor of mouth, or skin of face, that is, chin or nose; (oral cavity).Tumor invades adjacent structures only (e.g., through cortical bone into deep muscle of tongue, maxillary sinus, skin of face).
T4b Very advanced local disease. Tumor invades masticator space, pterygoid plates or skull base and/or encases internal carotid artery.
Node (N)
Nx Regional lymph nodes cannot be assessed.
N0 No regional lymph node metastasis.
N1 Metastasis to a single lymph node on same side as tumor, 3 cm or less in diameter.


Metastasis to a single lymph node on same side as tumor, more than 3 cm but not more than 6 cm in diameter; or in multiple lymph nodes on same side as tumor, none more than 6 cm in diameter; or in lymph nodes on opposite side or both sides, none more than 6 cm in diameter.
Metastasis to a single lymph node on same side as tumor more than 3 cm but not more than 6 cm in diameter.
Metastasis to multiple lymph nodes on same side as tumor, none more than 6 cm in diameter.
Metastasis to multiple lymph nodes on opposite side or both sides, none more than 6 cm in diameter.
N3 Metastasis to a lymph node, more than 6 cm in diameter.
Metastasis (M)
M0 No distant metastasis, has not spread to distant organs.
M1 Distant metastasis, has spread to distant organs.


Stages of oral cancer

Stage T N M
0 Tis N0 M0
I T1 N0 M0
II T2 N0 M0
T1 to T3
T1 to T4a
N0 or N1
Any T
Any N
IVC Any T Any N M1

Treatment options

Treatments for oral cancer include surgery, radiation therapy, chemotherapy and immunotherapy. Treatments may be used alone or in combination with one another, depending on the stage of your disease and your overall health.


Surgery is done to remove early-stage tumors and may include removal of any cancer that has possibly spread to the lymph nodes in the neck. Small cancers of the lip and cancers of the floor of the mouth, front of the tongue, inside of the cheek, gums and hard palate are often removed with surgery. Radiation therapy and chemotherapy may be added. Later- stage cancers are also treated with surgery. After surgery, reconstructive surgery may be recommended to repair damaged areas of the face and improve the ability to eat and talk (see Reconstruction).

Radiation therapy

Radiation therapy is sometimes used as a first-line treatment for cancer of the back of the tongue, soft palate and tonsils. It is also often recommended if the cancer has spread to bones or lymph nodes in the neck. Known as external-beam radiation therapy, this type of treatment uses a machine that aims high-energy beams of radiation, usually X-rays or gamma rays, at specific points of the body. External-beam radiation therapy is usually given for about six weeks, once a day for 15 to 30 minutes, five days a week.


Chemotherapy drugs, also called cytotoxic drugs, kill cells that divide quickly, such as cancer cells. Given alone or as a combination of two or more drugs, chemotherapy is a systemic therapy that works by killing cancer cells or stopping them from growing and spreading. It is sometimes used to treat metastatic oral cancer, and can be used with radiation therapy, a combination known as chemoradiation therapy. During chemoradiation, the chemotherapy drug is used to help make the cells more sensitive to the radiation.


Immunotherapy uses the body’s own immune system to slow and kill cancer cells. With this treatment approach, substances — made either by the body or in a laboratory — are used to identify cancer cells as a threat and target them for destruction.

Additional Resources


Previous Next


Register Now! Sign Up For Our Free E-Newletter!

Read Inspiring Cancer Survivor Stories

Order Your Guides Here