Floor of the mouth cancer


Learn about the symptoms of this type of cancer that forms under your tongue. Floor of the mouth cancer treatments include surgery, radiation and chemotherapy.


Floor of the mouth cancer is cancer that begins on the tissue underneath your tongue.

Floor of the mouth cancer most often begins in the thin, flat cells that line the inside of your mouth (squamous cells). Changes in the look and feel of the tissue on the floor of the mouth, such as a lump or a sore that doesn't heal, are often the first signs of floor of the mouth cancer.

Floor of the mouth cancer treatments include surgery, radiation therapy and chemotherapy.


Signs and symptoms of floor of the mouth cancer can include:

  • Mouth pain
  • Sores in your mouth that won't heal
  • Loose teeth
  • Pain when you swallow
  • Weight loss
  • Ear pain
  • Swelling in your neck that may hurt
  • White patches in your mouth that won't go away

When to see a doctor

Talk to your doctor or dentist about any persistent signs and symptoms that worry you.


Floor of the mouth cancer forms when a genetic mutation turns normal, healthy cells into abnormal cells. Healthy cells grow and multiply at a set rate, eventually dying at a set time. Abnormal cells grow and multiply out of control, and they don't die. The accumulating abnormal cells form a mass (tumor). Cancer cells invade nearby tissues and can separate from an initial tumor to spread (metastasize) to other parts of the body.


Things that may increase the rison of floor of the mouth cancer include:

  • Using tobacco
  • Drinking alcohol
  • Being infected with human papillomavirus (HPV)
  • Taking medications that suppress your immune system

If you use tobacco and drink alcohol, the risk is even higher.


Ways to reduce your risk of floor of the mouth cancer include:

  • Don't use tobacco. If you don't use tobacco, don't start. If you currently use tobacco of any kind, talk with your doctor about strategies to help you quit.
  • Limit alcohol if you choose to drink. If you choose to drink alcohol, do so in moderation. For healthy adults, that means up to one drink a day for women and up to two drinks a day for men.
  • Get regular dental care. During your appointment, your dentist will check your mouth for signs of cancer and precancerous changes.
  • Consider the HPV vaccine. Receiving a vaccination to prevent HPV infection may reduce your risk of HPV-related cancers, such as mouth cancer. Ask your doctor whether an HPV vaccine is appropriate for you.

Tests and procedures used to diagnose floor of the mouth cancer may include:

  • Thorough physical examination. The process starts with a physical exam and a discussion of your symptoms and medical history.
  • Removing a sample of tissue for testing (biopsy). Your doctor may remove a sample of suspicious cells from the floor of your mouth using a scalpel. Then your doctor sends the sample to a laboratory where experts analyze the cells to determine whether they're cancerous.
  • Imaging tests. Imaging tests help your doctor determine the extent of your cancer and whether it may have spread. Tests may include a CT, MRI and positron emission tomography (PET). Which tests you undergo depend on your particular situation.
  • Nutrition, speech and swallowing evaluations. Some people may need to meet with specialists in nutrition, speech and swallowing to determine next steps.

Treatments for floor of the mouth cancer include:

  • Surgery. The type of surgery used to treat floor of the mouth cancer depends on the size, type, location and depth of the tumor spread. If the tumor has spread beyond the floor of the mouth, nearby lymph nodes may need to be removed and examined to determine how far the cancer has spread.
  • Radiation therapy. Radiation therapy uses beams of intense energy, such as X-rays and protons, to kill cancer cells. Radiation may be used alone to treat small floor of the mouth cancers or it may be used after surgery to kill any cancer cells that might remain.
  • Chemotherapy. Chemotherapy uses drugs to destroy cancer cells. For people with floor of the mouth cancer, chemotherapy is often used after surgery to kill any cancer cells that might remain. Sometimes it's combined with radiation therapy.
  • Photodynamic therapy. In this therapy, your doctor will use a medication to make the cancer cells vulnerable to high-intensity light energy, such as from lasers. After the medication has been absorbed by the target tissue, your doctor will expose the cancer cells to a specific wavelength and energy of light that activates the drug and destroys the cancerous or precancerous cells.
  • Reconstructive surgery. Depending on the size, location and spread of the cancer, some people may need reconstructive surgery to restore mouth function.
  • Rehabilitation. Rehabilitation specialists in speech therapy, swallowing therapy, dietetics, physical therapy and occupational therapy help with rehabilitation that may be necessary after surgery or radiation therapy.
  • Palliative care. Palliative care is specialized medical care that focuses on providing relief from pain and other symptoms of a serious illness. Palliative care specialists work with you, your family and your other doctors to provide an extra layer of support that complements your ongoing care.

A cancer diagnosis can be overwhelming and frightening. You can help yourself feel more in control by taking an active role in your health care. To help you cope, try to:

  • Learn enough about cancer to make decisions about your care. Ask your doctor about your cancer, including the extent of your cancer, your treatment options and, if you like, your prognosis. As you learn more about cancer, you may become more confident in making treatment decisions.
  • Keep friends and family close. Keeping your close relationships strong will help you deal with your cancer. Friends and family can provide the practical support you'll need, such as helping take care of your home if you're in the hospital. And they can serve as emotional support when you feel overwhelmed by cancer.
  • Find someone to talk with. Find a good listener with whom you can talk about your hopes and fears. This may be a friend or family member. The concern and understanding of a counselor, medical social worker, clergy member or cancer support group also may be helpful.

    Ask your doctor about support groups in your area or contact cancer organizations, such as the National Cancer Institute or the American Cancer Society.


Make an appointment with your doctor or dentist if you have any signs or symptoms that worry you.

If your doctor or dentist feels you may have mouth cancer, you may be referred to a doctor who specializes in diseases of the face, mouth, teeth, jaws, salivary glands and neck (oral and maxillofacial surgeon) or to a doctor who specializes in diseases that affect the ears, nose and throat (ENT specialist or otorhinolaryngologist).

Because appointments can be brief, and because there's often a lot of ground to cover, it's a good idea to be well prepared. Here's some information to help you get ready.

What you can do

  • Be aware of any pre-appointment restrictions. At the time you make the appointment, be sure to ask if there's anything you need to do in advance, such as restrict your diet.
  • Write down symptoms you're experiencing, including any that may seem unrelated to the reason for which you scheduled the appointment.
  • Write down key personal information, including major stresses or recent life changes.
  • Make a list of all medications, vitamins or supplements you're taking.
  • Take a family member or friend along. Sometimes it can be difficult to remember all the information provided during an appointment. Someone who accompanies you may remember something that you missed or forgot.
  • Write down questions to ask your doctor.

Your time with your doctor is limited, so preparing a list of questions can help you make the most of your time together. List your questions from most important to least important in case time runs out. For floor of the mouth cancer, some basic questions to ask your doctor include:

  • What is the stage of my cancer?
  • What other tests do I need?
  • What are my treatment options?
  • Is there one treatment that's best for my type and stage of cancer?
  • What are the potential side effects for each treatment?
  • Should I seek a second opinion? Can you give me the names of specialists you recommend?
  • Am I eligible for clinical trials?
  • Are there brochures or other printed material that I can take with me? What websites do you recommend?
  • What will determine whether I should plan for a follow-up visit?

What to expect from your doctor

Your doctor is likely to ask you a number of questions. Being ready to answer them may allow time later to cover points you want to address. Your doctor may ask:

  • When did you begin experiencing symptoms?
  • Have your symptoms been continuous or occasional?
  • How severe are your symptoms?
  • What, if anything, seems to improve your symptoms?
  • What, if anything, appears to worsen your symptoms?


Last Updated:

August 12th, 2021

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