Oral Cancers

August 28, 2021

4 min read

According to the Oral Cancer Foundation (OCF), approximately 450,000 people (54,000 people in the US alone) are diagnosed with oral or oralpharygeal (mouth and throat) cancers each year. These cancers are a serious public health concern, because the death rate is higher than for other common cancers that people commonly hear about (e.g., cervical cancer, Hodgkin’s lymphoma, breast cancer, prostate cancer). Five years after diagnosis, 57% of patients with oral cancer will still be alive. Progress will continue to be made in new treatments, but the high death rate illustrates the importance of prevention and early detection, which increases the likelihood of sucessful treatment.

Oral cancers can form on any soft tissue in the oral cavity, including the tongue, gums, inside of the cheeks, roof of the mouth, and under the tongue. The cancers often begin in the cell layer that lines the inside of the moist areas of the mouth, called the squamous cells. While cancers can develop in the salivary glands, this is much rarer than with other oral structures.

Causes and Symptoms of Oral Cancers

Most oral cancers are associated with human papilloma virus (HPV) infection or chronic/heavy use of alcohol and tobacco. Extensive sun exposure also increases the risk of developing cancer on the lips. For all causes, the risk increases with age.

Common symptoms include:

White or red sores, lumps, or thick patches on the lips, mouth, or throat
A feeling that something is caught in the throat
Soreness, swelling, or numbness in the mouth or throat
Difficulty swallowing, chewing food, or talking
Dentures that no longer fit properly due to swollen tissues in the jaw
Ear pain

If any of these symptoms last more than 2 weeks, a doctor or dentist should be consulted to rule out the possibility of oral cancer. You can familiarize yourself with the kinds of lesions that may be oral cancer by viewing images on the website of the OCF.

Diagnosing Oral Cancers

Early detection is essential, because oral cancers can progress quickly. They have a tendency to spread, and the survival rate is best if treatment begins before the cancer has a chance to spread outside the mouth. Most dental offices perform a screen for oral cancers during routine cleaning appointments. A physical exam will check the inside of the cheeks, palate, lips, gum, and tongue for signs of irregular tissue. The neck lymph nodes will be checked to identify swelling (signs of an immune response against the cancer or spreading tumor cells). If an oral cancer is suspected, the dentist may refer you to a specialist for additional testing, which may include:

Taking a scrape of the inside of the mouth or lips to look under the microscope for abnormal looking cells.
Taking a biopsy (tissue sample) to look under the microscope for signs of cancer cells.
Imaging studies (e.g., x-rays, MRI, CT, PET) to understand the location of the tumor and extent of spread.

Cancers are staged to provide information about how advanced they are, which informs on the best treatment for the situation.

Stage 0 (carcinoma in situ): Abnormal cells are present but there is no tumor. These cells have the potential to become cancerous.
Stage 1: A tumor has formed. It is less than 2 centimeters (the size of a peanut) wide and it has reached 5 millimeters (width of a pencil eraser) or less into the surrounding tissue.
Stage 2: A tumor has formed. It is 2 centimeters or less but has reached more than 5 millimeters into the surrounding tissue; or it between 2 to 4 centimeters (the size of a peanut to a walnut) wide and has reached 10 millimeters (the size of a pea) or less into the surrounding tissue.
Stage 3: A tumor is found that meets one of the following criteria:
Between 2 and 4 centimeters wide and has reached at least 10 millimeters into the surrounding tissue.
Larger than 4 centimeters and has reached 10 millimeters or less into the surrounding tissue.
Has a secondary tumor in one lymph node on the same side of the body as the primary tumor. The secondary tumor is 3 centimeters (the size of a grape) or less.
Stage 4: This stage is further dividend into multiple substages of increasing severity (Stages 4A through 4D). In general, cancers in this stage are larger than 4 centimeters (the size of a walnut) and have spread beyond their original location.

Treating Oral Cancers

The treatment is highly individualized, depending on the size and type of tumor, and whether the cancer has spread to other parts of the body. Surgical removal of the oral tumor is often the first step in treatment. Radiation therapy and chemotherapy may also be used to kill any cancer cells left behind after the surgery. Depending on the extent of the cancer, dental surgeons may be needed to reconstruct damaged areas and restore function or improve cosmetic outcomes.

For some patients, clinical trials may be an option. These experimental therapies are not guaranteed to provide a benefit, but they contribute to the overall medical progress for treating these kinds of cancers. Clinical trials can involve experimental therapies aimed at curing or preventing the cancer from returning. Information on available clinical trials in the United States can be obtained from a physician or by looking at opportunities at the National Cancer Institute’s or FDAs ClinicalTrials.gov website.