Introduction
Overview
Description and Causes
Prevention and Treatment of Oral Complications Before Chemotherapy and/or Radiation Therapy Begins
Management of Oral Complications During and After Chemotherapy and/or Radiation Therapy

Routine Oral Care Oral Mucositis Infection Bleeding Dry Mouth Tooth Decay Taste Changes Fatigue Malnutrition and Nutritional Support Pain Jaw Stiffness Tissue and Bone Loss

Management of Oral Complications of High-Dose Chemotherapy and/or Stem Cell Transplant
Relapse and Second Cancers
Oral Complications Not Related to Chemotherapy or Radiation Therapy
Mental and Social Considerations
Special Considerations for Children
Get More Information From NCI
Changes to This Summary (11/06/2008)
Questions or Comments About This Summary
About PDQ

Introduction

This patient summary on oral complications of cancer and cancer therapy is adapted from the summary written for health professionals by cancer experts. This and other accurate, credible information about cancer treatment, screening, prevention, supportive care, and ongoing clinical trials is available from the National Cancer Institute. Oral complications are common in cancer patients, especially those with head and neck cancer. This summary describes oral complications caused by chemotherapy and radiation therapy and various methods of prevention and treatment.

Overview

Oral complications are common in patients receiving chemotherapy or undergoing radiation therapy to the head and neck.

The oral cavity is at high risk of side effects from chemotherapy and radiation therapy for a number of reasons.

• Chemotherapy and radiation therapy stop the growth of rapidly dividing cells, such as cancer cells. Since normal cells in the lining of the mouth also divide rapidly, anticancer treatment can prevent cells in the mouth from reproducing, making it difficult for oral tissue to repair itself.



• The mouth contains hundreds of different bacteria, some helpful and some harmful. Chemotherapy and radiation therapy can cause changes in the lining of the mouth and production of saliva and upset the healthy balance of bacteria. These changes may lead to mouth sores, infections, and tooth decay.



• Wear and tear occur from normal use of the mouth, teeth, and jaws, making healing more difficult.

Preventive measures may lessen the severity of oral complications.

Oral side effects may make it difficult for a patient to receive all of his or her cancer treatment. Sometimes treatment must be stopped. Preventing and controlling oral complications will enhance both the patient's quality of life and the effectiveness of cancer therapy.

Preventing and treating oral complications of cancer therapy involve identifying the patient at risk, starting preventive measures before cancer therapy begins, and treating complications as soon as they appear.

Description and Causes

Radiation therapy and chemotherapy may cause some of the same oral side effects, including the following:

• Mucositis (an inflammation of the mucous membranes in the mouth).
• Infections in the mouth or that travel through the bloodstream, reaching and affecting cells all over the body.
• Taste changes.
• Dry mouth.
• Pain.
• Changes in dental growth and development in children.
• Malnutrition (lack of nutrients needed by the body for health, often caused by the inability to eat).
• Dehydration (lack of water needed by the body for health, often caused by the inability to drink).
• Tooth decay and gum disease.

Complications may be caused directly or indirectly by anticancer therapy.

Oral complications associated with chemotherapy and radiation therapy may be caused directly by the treatment or may result indirectly from side effects of the treatment. Radiation therapy may directly damage oral tissue, salivary glands, and bone. Areas treated may scar or waste away.

Slow healing and infection are indirect complications of cancer treatment. Both chemotherapy and radiation therapy can affect the ability of cells to reproduce, which slows the healing process in the mouth. Chemotherapy may reduce the number of white blood cells and weaken the immune system (the organs and cells that defend the body against infection and disease), making it easier for the patient to develop an infection.

Complications can be acute or chronic.

Acute complications are those that occur during therapy. Chemotherapy usually causes acute complications that heal after treatment ends.

Chronic complications are those that continue or develop months to years after therapy ends. Radiation can cause acute complications but may also cause permanent tissue damage that puts the patient at a lifelong risk of oral complications. The following chronic complications commonly continue after radiation therapy to the head and/or neck has ended:

• Dry mouth.
• Tooth decay.
• Infections.
• Taste changes.
• Problems using the mouth and jaw due to tissue and bone loss and/or the growth of benign tumors in the skin and muscle.

Invasive dental procedures can cause additional problems. The dental care of patients who have undergone radiation therapy will therefore need to be adapted to the patient's ongoing complications.

Prevention and Treatment of Oral Complications Before Chemotherapy and/or Radiation Therapy Begins

Finding and treating oral problems before anticancer therapy begins can prevent or lessen the severity of oral complications.

Oral complications in patients undergoing treatment for head and neck cancer may be reduced by aggressive prevention measures taken before treatment begins. This will get the mouth and teeth in the best possible condition to withstand treatment.

Preventive measures include the following:

• Eating a well-balanced diet. Proper nutrition can help the body tolerate the stress of cancer treatment, maintain energy, fight infection, and rebuild tissue.



• Learning how to care for the mouth and teeth during and after anticancer therapy. Good dental hygiene helps prevent cavities, mouth sores, and infections.



• Having a complete oral health exam by a dentist familiar with the oral side effects of anticancer treatments.

The cancer care team should include the patient's dentist. It is important to choose a dentist familiar with the oral side effects of chemotherapy and/or radiation therapy. An evaluation of the patient's oral health at least a month before treatment begins usually provides enough time for the mouth to heal after dental work. The dentist will identify and treat teeth at risk for infection or decay, so the patient may avoid having invasive dental treatment during anticancer therapy. The dentist may also provide appropriate preventive care to lessen the severity of dry mouth, a common complication of radiation therapy to the head and neck.

A preventive oral health exam will check for the following:

• Mouth sores or infections.
• Tooth decay.
• Gum disease.
• Dentures that do not fit well.
• Problems moving the jaw.
• Problems with the salivary glands.

Patients undergoing high-dose chemotherapy, stem cell transplant, and/or radiation therapy need an oral care plan in place before treatment begins.

The goal of the oral care plan is to find and treat oral disease that may produce complications during treatment and to continue oral care throughout treatment and recovery. Different oral complications may occur during the different phases of transplantation. Steps can be taken ahead of time to prevent or lessen the severity of these side effects.

Ongoing oral care during radiation therapy will depend on the specific needs of the patient; the dose, locations, and duration of the radiation treatment; and the specific complications that occur.

It is important that patients who have head or neck cancer stop smoking.

Continued smoking slows recovery and increases the risk that the head or neck cancer will recur or that a second cancer will develop. (Refer to the PDQ summary on Smoking Cessation and Continued Risk in Cancer Patients ¹ for more information.)

Management of Oral Complications During and After Chemotherapy and/or Radiation Therapy

Routine Oral Care

Continuing good dental hygiene during and after cancer treatment can reduce complications such as cavities, mouth sores, and infections. It is important to clean the mouth after eating. The following are guidelines for everyday oral care during chemotherapy and radiation therapy:

Tooth brushing

• Brush teeth and gums with a soft bristle brush 2 to 3 times a day for 2 to 3 minutes.



• Rinse the toothbrush in hot water every 15 to 30 seconds to soften the bristles, if needed.



• If it is necessary to use a foam toothbrush, use it with an antibacterial rinse, when possible.



• Allow the toothbrush to air dry between brushings.



• Choose toothpaste with care:
  • Use a mild-tasting toothpaste; flavoring may irritate the mouth.
  • If toothpaste irritates the mouth, brush with a solution of 1 teaspoon of salt added to 4 cups (1 quart) of water.
  • Use a fluoride toothpaste.

Rinsing

• Rinse the mouth 3 or 4 times while brushing.
• Avoid rinses containing alcohol.
• One of the following rinses made with salt and/or baking soda may be used:
  • 1 teaspoon of salt in 4 cups of water.
  • 1 teaspoon of baking soda in 1 cup (8 ounces) of water.
  • ½ teaspoon salt and 2 tablespoons baking soda in 4 cups of water.
• An antibacterial rinse may be used 2 to 4 times a day for gum disease. Rinse for 1 to 2 minutes.
• If dry mouth occurs, rinsing may not be enough to clean the teeth after a meal. Brushing and flossing may be needed.

Flossing

• Floss gently once a day.

Lip care

• Use lip care products to prevent drying and cracking.

Mucositis is an inflammation of mucous membranes in the mouth.

The terms "oral mucositis" and "stomatitis" are often used in place of each other, but their meanings are different.

• Mucositis is an inflammation of mucous membranes in the mouth. It usually appears as red, burn-like sores or as ulcer -like sores throughout the mouth.



• Stomatitis is an inflammation of tissues in the mouth, such as the gums, tongue, roof and floor of the mouth, and tissues inside the lips and cheeks. It includes infections of mucous membranes.

Mucositis may be caused by either radiation therapy or chemotherapy. In patients receiving chemotherapy, mucositis will heal by itself, usually in 2 to 4 weeks when there is no infection. Mucositis caused by radiation therapy usually lasts 6 to 8 weeks, depending on the duration of treatment.

The following problems may occur:

• Pain.
• Infection.
• Bleeding, in patients receiving chemotherapy. Patients undergoing radiation therapy usually do not have a bleeding risk.
• Inability to breathe and eat normally.

Swishing ice chips in the mouth for 30 minutes may help prevent mucositis from developing in patients who are given fluorouracil. Medication may be given to help prevent mucositis or keep it from lasting as long in patients who undergo high-dose chemotherapy and bone marrow transplant.

Care of mucositis during chemotherapy and radiation therapy focuses on cleaning the mouth and relieving the symptoms.

Treatment of mucositis caused by either radiation therapy or chemotherapy is generally the same. After mucositis has developed, proper treatment depends on its severity and the patient's white blood cell count. The following are guidelines for treating mucositis during chemotherapy, stem cell transplantation, and radiation therapy:

Cleaning the mouth

• Clean the teeth and mouth every 4 hours and at bedtime, more often if the mucositis becomes worse.



• Use a soft bristle toothbrush.



• Replace the toothbrush often.



• Use water-soluble lubricating jelly to moisturize the mouth.



• Use bland rinses or plain sterile water. Frequent rinsing removes particles and bacteria from the mouth, prevents crusting of sores, and moistens and soothes sore gums and the lining of the mouth. The following rinse may be used to neutralize acid and dissolve thick saliva:
  • ½ teaspoon salt and 2 tablespoons baking soda in 4 cups of water.



• If crusting of sores occurs, the following rinse may be used:
  • Equal parts hydrogen peroxide and water or saltwater (1 teaspoon of salt in 4 cups of water).
  This should not be used for more than 2 days because it will keep mucositis from healing.

Relieving pain

• Try topical medications for pain. Rinse the mouth before applying the medication onto the gums or lining of the mouth. Wipe mouth and teeth gently with wet gauze dipped in saltwater to remove particles.



• Painkillers may provide relief when topical medications do not. Nonsteroidal anti-inflammatory drugs (NSAIDS, aspirin -type painkillers) should not be used by patients receiving chemotherapy because these patients have a bleeding risk.



• Capsaicin, the active ingredient in hot peppers, may be used to increase a person's ability to tolerate pain. When capsaicin is put on inflamed tissues in the mouth, mucositis pain may decrease as the burning feeling from the capsaicin decreases. The side effects of capsaicin are not known.



• Zinc supplements taken during radiation therapy may help treat mucositis as well as dermatitis (inflammation of the skin).



• Povidone- iodine mouthwash that does not contain alcohol may help delay or decrease mucositis caused by radiation therapy.

Damage to the lining of the mouth and a weakened immune system make it easier for infection to occur.

Oral mucositis breaks down the lining of the mouth, allowing germs and viruses to get into the bloodstream. When the immune system is weakened by chemotherapy, even good bacteria in the mouth can cause infections, as can disease-causing organisms picked up from the hospital or other sources. As the white blood cell count gets lower, infections may occur more often and become more serious. Patients who have low white blood cell counts for a long time are more at risk of developing serious infections. Dry mouth, common during radiation therapy to the head and neck, may also raise the risk of infections in the mouth. Preventive dental care during chemotherapy and radiation therapy can reduce the risk of mouth, tooth, and gum infections.

The following types of infections may occur:

Bacterial infections

Treatment of bacterial infections in patients who have gum disease and receive high-dose chemotherapy may include the following:

• Medicated and peroxide mouth rinses.
• Brushing and flossing.
• Wearing dentures as little as possible.

Bacterial infections in patients undergoing radiation therapy are usually treated with antibiotics.

Fungal infections

The mouth normally contains fungi that can exist on or in the body without causing any problems. An overgrowth of fungi, however, can be serious and requires treatment.

Antibiotics and steroid drugs are often used when a patient receiving chemotherapy has a low white blood cell count. These drugs change the balance of bacteria in the mouth, making it easier for a fungal overgrowth to occur. Fungal infections are common in patients treated with radiation therapy.

Drugs may be given to prevent fungal infections from occurring. Treatment of surface fungal infections in the mouth only may include mouthwashes and lozenges that contain antifungal drugs. These are used after removing dentures, brushing the teeth, and cleaning the mouth. An antibacterial rinse should be used on dentures and dental appliances and to rinse the mouth.

Deeper fungal infections, such as those in the esophagus or intestines, are treated with drugs taken by mouth or injection.

Viral infections

Patients receiving chemotherapy, especially those with weakened immune systems, are at risk of mild to serious viral infections. Finding and treating the infections early is important. Drugs may be used to prevent or treat viral infections.

Herpesvirus infections may recur in radiation therapy patients who have these infections.

Bleeding may occur during chemotherapy when anticancer drugs affect the ability of blood to clot.

Areas of gum disease may bleed on their own or when irritated by eating, brushing, or flossing. Bleeding may be mild (small red spots on the lips, soft palate, or bottom of the mouth) or severe, especially at the gumline and from ulcers in the mouth. When blood counts drop below certain levels, blood may ooze from the gums.

With close monitoring, most patients can safely brush and floss throughout the entire time of decreased blood counts.

Continuing regular oral care will help prevent infections that may further complicate bleeding problems. The dentist or doctor can provide guidance on how to treat bleeding and safely keep the mouth clean when blood counts are low.

Treatment for bleeding during chemotherapy may include the following:

• Medications to reduce blood flow and help clots form.
• Topical products that cover and seal bleeding areas.
• Rinsing with a mixture of one part 3% hydrogen peroxide to 2 or 3 parts saltwater solution (1 teaspoon of salt in 4 cups of water) to help clean oral wounds. Rinsing must be done carefully so clots are not disturbed.

Dry mouth (xerostomia) occurs when the salivary glands produce too little saliva.

Saliva is needed for taste, swallowing, and speech. It helps prevent infection and tooth decay by neutralizing acid and cleaning the teeth and gums. Radiation therapy can damage salivary glands, causing them to make too little saliva. When dry mouth (xerostomia) develops, the patient's quality of life suffers. The mouth is less able to clean itself. Acid in the mouth is not neutralized, and minerals are lost from the teeth. Tooth decay and gum disease are more likely to develop. In addition, there is some evidence that salivary glands may be damaged by certain types of chemotherapy drugs given alone or in combination. Symptoms of dry mouth include the following:

• Thick, stringy saliva.
• Increased thirst.
• Changes in taste, swallowing, and speech.
• A sore or burning feeling (especially on the tongue).
• Cuts or cracks in the lips or at the corners of the mouth.
• Changes in the surface of the tongue.
• Difficulty wearing dentures.

Salivary glands may not recover completely after radiation therapy ends.

Saliva production drops within 1 week after starting radiation therapy to the head and/or neck and continues to decrease as treatment continues. The severity of dry mouth depends on the dose of radiation and the number of glands irradiated. The salivary glands in the upper cheeks near the ears are more affected than other salivary glands.

Partial recovery of salivary glands may occur in the first year after radiation therapy, but recovery is usually not complete, especially if the salivary glands were directly irradiated. Salivary glands that were not irradiated may become more active to offset the loss of saliva from the destroyed glands.

Careful oral hygiene can help prevent mouth sores, gum disease, and tooth decay caused by dry mouth.

The following are guidelines for managing dry mouth:

• Clean the mouth and teeth at least 4 times a day.
• Floss once a day.
• Use a fluoride toothpaste when brushing.
• Apply fluoride gel once a day at bedtime, after cleaning the teeth.
• Rinse 4 to 6 times a day with a solution of salt and baking soda (mix ½ teaspoon salt and ½ teaspoon baking soda in 1 cup of warm water). Avoid foods and liquids that contain a lot of sugar. Sip water to relieve mouth dryness.

A dentist can provide the following treatments:

• Solutions to replace minerals in the teeth.
• Rinses to fight infection in the mouth.
• Saliva substitutes or medications to stimulate the salivary glands.
• Fluoride treatments to prevent tooth decay.

Dry mouth and changes in the balance of oral bacteria increase the risk of tooth decay. Meticulous oral hygiene (as described in Routine Oral Care ²) and regular care by a dentist can help prevent cavities.

Changes in taste are common during chemotherapy and radiation therapy.

Change in the sense of taste (dysgeusia) is a common side effect of both chemotherapy and head and/or neck radiation therapy. Foods may have no taste or may not taste as they did before therapy. These taste changes are caused by damage to the taste buds, dry mouth, infection, and/or dental problems. Chemotherapy patients may experience unpleasant taste related to the spread of the drug within the mouth. Radiation may cause a change in sweet, sour, bitter, and salty tastes.

In most patients receiving chemotherapy and in some patients undergoing radiation therapy, taste returns to normal a few months after therapy ends. For many radiation therapy patients, however, the change is permanent. In others, the taste buds may recover 6 to 8 weeks, or later, after radiation therapy ends. Zinc sulfate supplements may help with the recovery for some patients.

Cancer patients who are undergoing high-dose chemotherapy and/or radiation therapy often experience fatigue (lack of energy) that is related to either the cancer or its treatment. Some patients may have difficulty sleeping. The patient may feel too tired to perform routine oral care, which may further increase the risk for mouth ulcers, infection, and pain. (Refer to the PDQ summary on Fatigue ³ for more information.)

Loss of appetite can lead to malnutrition.

Patients undergoing treatment for head and neck cancers are at high risk for malnutrition. The cancer itself, poor diet before diagnosis, and complications from surgery, radiation therapy, and chemotherapy can lead to nutritional shortfalls. Patients can lose the desire to eat due to nausea, vomiting, trouble swallowing, sores in the mouth, or dry mouth. When eating causes discomfort or pain, the patient's quality of life and nutritional well-being suffer. The following suggestions may help patients with cancer meet their nutritional needs:

• Change the texture of food. Serving food chopped, ground, or blended can reduce the amount of time it needs to stay in the mouth before being swallowed.
• Eat between-meal snacks to add calories and nutrients.
• Choose foods high in calories and protein.
• Take supplements that provide vitamins, minerals, and calories.

Nutritional counseling may be helpful during and after treatment.

Nutritional support may include liquid diets and enteral feedings.

Many patients treated for head and neck cancers who receive radiation therapy alone are able to eat soft foods. As treatment progresses, most patients will include or switch to liquid diets using high-calorie, high-protein nutritional drinks. Some patients may need enteral tubefeeding to meet their nutritional needs. Almost all patients who receive chemotherapy and head and/or neck radiation therapy at the same time will require enteral nutritional support within 3 to 4 weeks. Studies show that patients benefit when they begin enteral feedings at the start of treatment, before weight loss occurs.

Normal eating by mouth begins again when treatment is finished and the site that received radiation is healed. The return to normal eating often needs a team approach, including a speech and swallowing therapist to ease the adjustment back to solid foods. Tubefeedings are decreased as a patient's intake by mouth increases, and are stopped when the patient is able to get enough nutrients by mouth. Although most patients will regain their ability to eat solid foods, many will have lasting complications such as taste changes, dry mouth, and trouble swallowing. These complications can interfere with meeting their nutritional needs and with their quality of life.

Certain anticancer drugs can cause nerve damage that may result in oral pain.

If an anticancer drug is causing the pain, stopping the drug usually stops the pain. Because there may be many causes of oral pain during cancer treatment, a careful diagnosis is important. This may include obtaining a medical history, performing physical and dental exams, and taking x-rays of the teeth.

Tooth sensitivity may occur in some patients weeks or months after chemotherapy has ended. Fluoride treatments and/or toothpaste for sensitive teeth may relieve the discomfort.

Pain in the teeth or jaw muscles may occur from tooth grinding or stress.

Pain in the teeth or jaw muscles may occur in patients who grind their teeth or clench their jaws, often because of stress or the inability to sleep. Treatment may include the following:

• Muscle relaxers.
• Drugs to treat anxiety.
• Physical therapy (moist heat, massage, and stretching).
• Mouthguards to wear while sleeping.

A long-term complication of radiation therapy is the growth of benign tumors in the skin and muscles. These tumors may make it difficult for the patient to move the mouth and jaw normally. Oral surgery may also affect jaw mobility. Management of jaw stiffness may include the following:

• Physical therapy.
• Oral appliances.
• Pain treatments.
• Medication.

Radiation therapy can cause tissue and bone in the treated area to waste away. When tissue death occurs, ulcers may form in the soft tissues of the mouth, grow in size, and cause pain or loss of feeling. Infection becomes a risk. As bone tissue is lost, fractures can occur. Preventive care can lessen the severity of tissue and bone loss.

Treatment of tissue and bone loss may include the following:

• Eating a well-balanced diet.
• Wearing removable dentures or appliances as little as possible.
• Not smoking.
• Not drinking alcohol.
• Using topical antibiotics.
• Using painkillers.
• Undergoing surgery to remove dead bone or to reconstruct bones of the mouth and jaw.
• Receiving hyperbaric oxygen therapy, a method of delivering oxygen under pressure to the surface of a wound to help it heal.

(Refer to Nutrition in Cancer Care ⁴ for more information about managing mouth sores, dry mouth, and taste changes.)

Management of Oral Complications of High-Dose Chemotherapy and/or Stem Cell Transplant

Patients who have received transplants are at risk of graft-versus-host disease.

Graft-versus-host disease (GVHD) is a reaction of donated bone marrow or stem cells against the patient's tissue. Symptoms of oral GVHD include the following:

• Sores that appear in the mouth 2 to 3 weeks after the transplant.
• Dry mouth.
• Pain from spices, alcohol, or flavoring (such as mint in toothpaste).

Biopsies taken from the lining of the mouth and salivary glands may be needed to diagnose oral GVHD. Treatment of oral GVHD may include the following:

• Topical rinses, gels, creams, or powders.
• Antifungal drugs taken by mouth or injection.
• Psoralen (a drug used with ultraviolet light to treat skin disease).
• Drugs that promote the production of saliva.
• Fluoride treatments.
• Treatments to replace minerals lost from teeth by acids in the mouth.

Dentures, braces, and oral appliances require special care during high-dose chemotherapy and/or stem cell transplant.

The following are guidelines for the care and use of dentures, braces, and other oral appliances during high-dose chemotherapy and/or stem cell transplant:

• Remove brackets, wires, and retainers before high-dose chemotherapy begins.



• Wear dentures only when eating during the first 3 to 4 weeks after the transplant.



• Brush dentures twice a day and rinse them well.



• Soak dentures in an antibacterial solution when they are not being worn.



• Clean denture soaking cups and change denture soaking solution every day.



• Remove appliances or dentures when cleaning the mouth.



• If mouth sores are present, avoid wearing removable appliances until the mouth is healed.

Dental treatments may be resumed when the transplant patient's immune system returns to normal.

Routine dental treatments, including scaling and polishing, should be delayed until the transplant patient's immune system returns to normal. Caution is advised for at least a year after the transplant.

Relapse and Second Cancers

Cancer survivors who received chemotherapy or a transplant or who underwent radiation therapy are at risk of developing a second cancer later in life. Oral squamous cell cancer is the most common second cancer occurring in transplant patients. The lips and tongue are the sites most often affected.

Oral Complications Not Related to Chemotherapy or Radiation Therapy

Bisphosphonates are drugs taken by some cancer patients to treat bone-related side effects.

Bisphosphonates are drugs given to some patients whose cancer has spread to the bones. They are used to reduce pain and decrease the risk of broken bones. (See the PDQ summary on Pain ⁵ for more information.) Bisphosphonates are also used to treat hypercalcemia (too much calcium in the blood). Some cancer cells secrete substances that cause calcium to be absorbed into the bloodstream from bones. (See the PDQ summary on Hypercalcemia ⁶ for more information.)

Certain bisphosphonates are linked to a risk of bone loss.

Certain bisphosphonates are linked to the breakdown of bone in the mouth, usually the jaw. This is called bisphosphonate-associated osteonecrosis (BON). It occurs more often in patients taking intravenous bisphosphonates, but it sometimes develops in patients taking them by mouth. Symptoms include pain and inflamed lesions in the mouth, where areas of damaged bone may be seen. There are many patients who take bisphosphonates, but the number who develop BON is small.

BON most commonly occurs after oral surgery.

BON most commonly occurs after a dental procedure such as having a tooth pulled. The area fails to heal for weeks after the procedure. If not treated, the areas of bone loss and the lesions can become very large and infected. These patients may develop paresthesia, an abnormal feeling on the skin, such as burning or prickling, that occurs without any known physical cause. Patients with severe BON may need to be treated in a hospital or have part of the jawbone removed.

It is less common for BON to occur in patients who have not had dental procedures.

Treatment of BON usually includes treating the infection and good dental hygiene.

Treatment of BON may include the following:

• Removing the infected tissue.
• Smoothing sharp edges of exposed bone.
• Taking antibiotics to fight infection.
• Using medicated mouth rinses.

During treatment for BON, the patient should continue to brush and floss the teeth after meals to keep the mouth very clean. Avoiding tobacco use while BON is healing may be advised.

Stopping the use of the bisphosphonate is a decision to be made by the patient and doctor, based on the effect it would have on the patient's general health.

New types of bisphosphonates are being studied in clinical trials. The use of hyperbaric oxygen therapy (HBO) combined with stopping the use of bisphosphonates is under study for the treatment of BON. It is not known if tobacco use increases the risk of developing BON.

Mental and Social Considerations

The social aspects of oral complications can make them the most difficult problems for cancer patients to cope with. Oral complications affect eating and speaking and may make the patient unable or unwilling to take part in mealtimes or to dine out. Patients may become frustrated, withdrawn, or depressed, and they may avoid other people. Some drugs that are used to treat depression may not be an option because they cause side effects that make oral complications worse. (Refer to the PDQ summaries on Anxiety ⁷ and Depression ⁸ for more information.)

Education, supportive care, and the treatment of symptoms are important for patients who have mouth problems that are related to cancer therapy. Patients will be closely monitored for pain, ability to cope, and response to treatment. Supportive care from health care providers and family can help the patient cope with cancer and its complications.

Special Considerations for Children

A change in dental growth and development is a special complication for cancer survivors who received high-dose chemotherapy and/or radiation therapy to the head and neck for childhood cancers. Changes may occur in the size and shape of the teeth; eruption of teeth may be delayed; and development of the head and face may not reach full maturity. The role and timing of orthodontic treatment for patients with altered dental growth and development is under study. Some treatments have been successful, but standard guidelines have not yet been established.

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Changes to This Summary (11/06/2008)

The PDQ cancer information summaries are reviewed regularly and updated as new information becomes available. This section describes the latest changes made to this summary as of the date above.

Changes were made to this summary to match those made to the health professional version.

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About PDQ

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PDQ is the National Cancer Institute's (NCI's) comprehensive cancer information database. Most of the information contained in PDQ is available online at NCI's Web site ¹⁰. PDQ is provided as a service of the NCI. The NCI is part of the National Institutes of Health, the federal government's focal point for biomedical research.

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PDQ also contains information on clinical trials.

A clinical trial is a study to answer a scientific question, such as whether one method of treating symptoms is better than another. Trials are based on past studies and what has been learned in the laboratory. Each trial answers certain scientific questions in order to find new and better ways to help cancer patients. Some patients have symptoms caused by cancer treatment or by the cancer itself. During supportive care clinical trials, information is collected about how well new ways to treat symptoms of cancer work. The trials also study side effects of treatment and problems that come up during or after treatment. If a clinical trial shows that a new treatment is better than one currently being used, the new treatment may become "standard." Patients who have symptoms related to cancer treatment may want to think about taking part in a clinical trial.

Listings of clinical trials are included in PDQ and are available online at NCI's Web site ¹³. Descriptions of the trials are available in health professional and patient versions. Many cancer doctors who take part in clinical trials are also listed in PDQ. For more information, call the Cancer Information Service 1-800-4-CANCER (1-800-422-6237); TTY at 1-800-332-8615.

Glossary Terms

Not normal. An abnormal lesion or growth may be cancerous, premalignant (likely to become cancer), or benign.

Symptoms or signs that begin and worsen quickly; not chronic.

A chemical substance found in beer, wine, and liquor. Alcohol is also found in some medicines, mouthwashes, essential oils (scented liquid taken from plants), and household products.

A substance that kills bacteria or stops them from growing and causing disease.

A drug used to treat infections caused by bacteria and other microorganisms.

A drug that treats infections caused by fungi.

Feelings of fear, dread, and uneasiness that may occur as a reaction to stress. A person with anxiety may sweat, feel restless and tense, and have a rapid heart beat. Extreme anxiety that happens often over time may be a sign of an anxiety disorder.

A drug that reduces pain, fever, inflammation, and blood clotting. Aspirin belongs to the family of drugs called nonsteroidal anti-inflammatory agents. It is also being studied in cancer prevention.

A large group of single-cell microorganisms. Some cause infections and disease in animals and humans. The singular of bacteria is bacterium.

A noncancerous growth that does not invade nearby tissue or spread to other parts of the body.

The removal of cells or tissues for examination by a pathologist. The pathologist may study the tissue under a microscope or perform other tests on the cells or tissue. There are many different types of biopsy procedures. The most common types include: (1) incisional biopsy, in which only a sample of tissue is removed; (2) excisional biopsy, in which an entire lump or suspicious area is removed; and (3) needle biopsy, in which a sample of tissue or fluid is removed with a needle. When a wide needle is used, the procedure is called a core biopsy. When a thin needle is used, the procedure is called a fine-needle aspiration biopsy.

A drug or substance used to treat hypercalcemia (abnormally high blood calcium) and bone pain caused by some types of cancer. Forms of bisphosphonates are also used to treat osteoporosis and for bone imaging. Bisphosphonates inhibit a type of bone cell that breaks down bone. Also called diphosphonate.

The necrosis (death) of bone tissue caused by treatment with a bisphosphonate (a drug or substance used to treat osteoporosis, bone pain caused by some types of cancer, and high blood calcium). It commonly occurs in the jaw bones. There may be pain, swelling and infection in the areas of necrosis. Also called BON.

A tissue with red blood cells, white blood cells, platelets, and other substances suspended in fluid called plasma. Blood takes oxygen and nutrients to the tissues, and carries away wastes.

A test to check the number of red blood cells, white blood cells, and platelets in a sample of blood. Also called CBC and complete blood count.

A mass of blood that forms when blood platelets, proteins, and cells stick together. When a blood clot is attached to the wall of a blood vessel, it is called a thrombus. When it moves through the bloodstream and blocks the flow of blood in another part of the body, it is called an embolus.

The soft, sponge-like tissue in the center of most bones. It produces white blood cells, red blood cells, and platelets.

A procedure to replace bone marrow that has been destroyed by treatment with high doses of anticancer drugs or radiation. Transplantation may be autologous (an individual's own marrow saved before treatment), allogeneic (marrow donated by someone else), or syngeneic (marrow donated by an identical twin).

A mineral found in teeth, bones, and other body tissues.

A measurement of the energy content of food. The body needs calories as to perform its functions, such as breathing, circulating the blood, and physical activity. When a person is sick, their body may need extra calories to fight fever or other problems.

A term for diseases in which abnormal cells divide without control. Cancer cells can invade nearby tissues and can spread to other parts of the body through the blood and lymph systems. There are several main types of cancer. Carcinoma is cancer that begins in the skin or in tissues that line or cover internal organs. Sarcoma is cancer that begins in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue. Leukemia is cancer that starts in blood-forming tissue such as the bone marrow, and causes large numbers of abnormal blood cells to be produced and enter the blood. Lymphoma and multiple myeloma are cancers that begin in the cells of the immune system. Central nervous system cancers are cancers that begin in the tissues of the brain and spinal cord.

A component of certain plants, including cayenne and red pepper, used topically for peripheral nerve pain. It is also being studied for controlling mucositis pain after chemotherapy and radiation therapy.

A hollow area or hole. It may describe a body cavity (such as the space within the abdomen) or a hole in a tooth caused by decay.

The individual unit that makes up the tissues of the body. All living things are made up of one or more cells.

Treatment with drugs that kill cancer cells.

A disease or condition that persists or progresses over a long period of time.

A type of research study that tests how well new medical approaches work in people. These studies test new methods of screening, prevention, diagnosis, or treatment of a disease. Also called clinical study.

Treatment using more than one anticancer drug.

In medicine, a medical problem that occurs during a disease, or after a procedure or treatment. The complication may be caused by the disease, procedure, or treatment or may be unrelated to them.

To adjust to new situations and overcome problems.

A condition caused by the loss of too much water from the body. Severe diarrhea or vomiting can cause dehydration.

A health professional who specializes in caring for the teeth, gums, and other tissues in the mouth.

A mental condition marked by ongoing feelings of sadness, despair, loss of energy, and difficulty dealing with normal daily life. Other symptoms of depression include feelings of worthlessness and hopelessness, loss of pleasure in activities, changes in eating or sleeping habits, and thoughts of death or suicide. Depression can affect anyone, and can be successfully treated. Depression affects 15-25% of cancer patients.

Inflammation of the skin.

The process of identifying a disease, such as cancer, from its signs and symptoms.

The things a person eats and drinks.

The amount of medicine taken, or radiation given, at one time.

Any substance, other than food, that is used to prevent, diagnose, treat or relieve symptoms of a disease or abnormal condition. Also refers to a substance that alters mood or body function, or that can be habit-forming or addictive, especially a narcotic.

A bad taste in the mouth. Also called parageusia.

A form of nutrition that is delivered into the digestive system as a liquid. Drinking nutrition beverages or formulas and tubefeeding are forms of enteral nutrition. People who are unable to meet their needs with food and beverages alone, and who do not have vomiting or uncontrollable diarrhea may be given tubefeedings. Tubefeeding can be used to add to what a person is able to eat or can be the only source of nutrition. A small feeding tube may be placed through the nose into the stomach or the small intestine, or it may be surgically placed into the stomach or the intestinal tract through an opening made on the outside of the abdomen, depending on how long it will be used.

The muscular tube through which food passes from the throat to the stomach.

A condition marked by extreme tiredness and inability to function due lack of energy. Fatigue may be acute or chronic.

A form of the element fluorine that helps prevent tooth decay. Fluoride may be naturally present in drinking water or may be added to it. Fluoride may also be put directly on the teeth, as a gel, toothpaste, or a rinse.

A drug used in the treatment of cancer. It is a type of antimetabolite. Also called 5-FU.

A plant-like organism that does not make chlorophyll. Mushrooms, yeasts, and molds are examples. The plural is fungi.

A disease caused when cells from a donated stem cell graft attack the normal tissue of the transplant patient. Symptoms include jaundice, skin rash or blisters, a dry mouth, or dry eyes. Also called GVHD.

The tissue of the upper and lower jaws that surrounds the base of the teeth. Also called gingiva.

Cancer that arises in the head or neck region (in the nasal cavity, sinuses, lips, mouth, salivary glands, throat, or larynx [voice box]).

A member of the herpes family of viruses.

An intensive drug treatment to kill cancer cells, but that also destroys the bone marrow and can cause other severe side effects. High-dose chemotherapy is usually followed by bone marrow or stem cell transplantation to rebuild the bone marrow.

A chemical used in bleaches, dyes, cleansers, antiseptics, and disinfectants. In a concentrated form, it is toxic and irritating to tissues.

The science of health, and the practice of cleanliness that promotes good health and well-being.

Oxygen that is at an atmospheric pressure higher than the pressure at sea level. Breathing hyperbaric oxygen to enhance the effectiveness of radiation therapy is being studied.

Higher than normal levels of calcium in the blood. Some types of cancer increase the risk of hypercalcemia.

The complex group of organs and cells that defends the body against infections and other diseases.

Invasion and multiplication of germs in the body. Infections can occur in any part of the body and can spread throughout the body. The germs may be bacteria, viruses, yeast, or fungi. They can cause a fever and other problems, depending on where the infection occurs. When the body’s natural defense system is strong, it can often fight the germs and prevent infection. Some cancer treatments can weaken the natural defense system.

Redness, swelling, pain, and/or a feeling of heat in an area of the body. This is a protective reaction to injury, disease, or irritation of the tissues.

Use of a syringe and needle to push fluids or drugs into the body; often called a "shot."

The long, tube-shaped organ in the abdomen that completes the process of digestion. The intestine has two parts, the small intestine and the large intestine. Also called bowel.

Into or within a vein. Intravenous usually refers to a way of giving a drug or other substance through a needle or tube inserted into a vein. Also called I.V..

A medical procedure that invades (enters) the body, usually by cutting or puncturing the skin or by inserting instruments into the body.

An element that is necessary for the body to make thyroid hormone. It is found in shellfish and iodized salt.

Treated with radiation.

An area of abnormal tissue. A lesion may be benign (noncancerous) or malignant (cancerous).

A disorder caused by a lack of proper nutrition or an inability to absorb nutrients from food.

A treatment in which the soft tissues of the body are kneaded, rubbed, tapped, and stroked. Massage therapy may help people relax, relieve stress and pain, lower blood pressure, and improve circulation. It is being studied in the treatment of cancer symptoms such as lack of energy, pain, swelling, and depression.

A legal drug that is used to prevent, treat, or relieve symptoms of a disease or abnormal condition.

In medicine, a mineral is a nutrient that is needed in small amounts to keep the body healthy. Mineral nutrients include the elements calcium, magnesium, and iron.

A complication of some cancer therapies in which the lining of the digestive system becomes inflamed. Often seen as sores in the mouth.

The moist, inner lining of some organs and body cavities (such as the nose, mouth, lungs, and stomach). Glands in the mucous membrane make mucus (a thick, slippery fluid). Also called mucosa.

The National Cancer Institute, part of the National Institutes of Health of the United States Department of Health and Human Services, is the Federal Government's principal agency for cancer research. The National Cancer Institute conducts, coordinates, and funds cancer research, training, health information dissemination, and other programs with respect to the cause, diagnosis, prevention, and treatment of cancer. Access the National Cancer Institute Web site at http://www.cancer.gov. Also called NCI.

A feeling of sickness or discomfort in the stomach that may come with an urge to vomit. Nausea is a side effect of some types of cancer therapy.

A drug that decreases fever, swelling, pain, and redness. Also called NSAID.

A chemical compound (such as protein, fat, carbohydrate, vitamin, or mineral) contained in foods. These compounds are used by the body to function and grow.

The taking in and use of food and other nourishing material by the body. Nutrition is a 3-part process. First, food or drink is consumed. Second, the body breaks down the food or drink into nutrients. Third, the nutrients travel through the bloodstream to different parts of the body where they are used as "fuel" and for many other purposes. To give the body proper nutrition, a person has to eat and drink enough of the foods that contain key nutrients.

A process by which a health professional with special training in nutrition helps people make healthy food choices and form healthy eating habits. In cancer treatment, the goal of nutritional counseling is to help patients stay healthy during and after treatment and to stay strong enough to fight infections and the recurrence of disease. Also called dietary counseling.

By or having to do with the mouth.

The mouth.

A part of the body that performs a specific function. For example, the heart is an organ.

A measure of weight (one-sixteenth pound) and volume (one-eighth cup).

A colorless, odorless gas. It is needed for animal and plant life. Oxygen that is breathed in enters the blood from the lungs and travels to the tissues.

An abnormal touch sensation, such as burning or prickling, that occurs without an outside stimulus.

PDQ is an online database developed and maintained by the National Cancer Institute. Designed to make the most current, credible, and accurate cancer information available to health professionals and the public, PDQ contains peer-reviewed summaries on cancer treatment, screening, prevention, genetics, complementary and alternative medicine, and supportive care; a registry of cancer clinical trials from around the world; and directories of physicians, professionals who provide genetics services, and organizations that provide cancer care. Most of this information, and more specific information about PDQ, can be found on the NCI's Web site at http://www.cancer.gov/cancertopics/pdq. Also called Physician Data Query.

An exam of the body to check for general signs of disease.

The use of exercises and physical activities to help condition muscles and restore strength and movement. For example, physical therapy can be used to restore arm and shoulder movement and build back strength after breast cancer surgery.

Medical doctor.

In medicine, action taken to decrease the chance of getting a disease or condition. For example, cancer prevention includes avoiding risk factors (such as smoking, obesity, lack of exercise, and radiation exposure) and increasing protective factors (such as getting regular physical activity, staying at a healthy weight, and having a healthy diet).

Used to prevent disease.

A molecule made up of amino acids that are needed for the body to function properly. Proteins are the basis of body structures such as skin and hair and of substances such as enzymes, cytokines, and antibodies.

A substance from plants that is sensitive to light (or can be activated by light). Psoralens are used together with UV light to treat psoriasis, vitiligo, and skin nodules of cutaneous T-cell lymphoma. They are also being studied in the treatment of graft-versus-host disease. Psoralen is a type of furocoumarin. An example of a psoralen is methoxsalen.

The overall enjoyment of life. Many clinical trials assess the effects of cancer and its treatment on the quality of life. These studies measure aspects of an individual’s sense of well-being and ability to carry out various activities.

Energy released in the form of particle or electromagnetic waves. Common sources of radiation include radon gas, cosmic rays from outer space, medical x-rays, and energy given off by a radioisotope (unstable form of a chemical element that releases radiation as it breaks down and becomes more stable).

The use of high-energy radiation from x-rays, gamma rays, neutrons, protons, and other sources to kill cancer cells and shrink tumors. Radiation may come from a machine outside the body (external-beam radiation therapy), or it may come from radioactive material placed in the body near cancer cells (internal radiation therapy). Systemic radiation therapy uses a radioactive substance, such as a radiolabeled monoclonal antibody, that travels in the blood to tissues throughout the body. Also called irradiation and radiotherapy.

To come back or to return.

In medicine, an improvement related to treatment.

The watery fluid in the mouth made by the salivary glands. Saliva moistens food to help digestion and it helps protect the mouth against infections.

A gland in the mouth that produces saliva.

Checking for disease when there are no symptoms. Since screening may find diseases at an early stage, there may be a better chance of curing the disease. Examples of cancer screening tests are the mammogram (breast), colonoscopy (colon), Pap smear (cervix), and PSA blood level and digital rectal exam (prostate). Screening can also include checking for a person’s risk of developing an inherited disease by doing a genetic test.

Refers to a new primary cancer in a person with a history of cancer.

A problem that occurs when treatment affects healthy tissues or organs. Some common side effects of cancer treatment are fatigue, pain, nausea, vomiting, decreased blood cell counts, hair loss, and mouth sores.

The back, muscular (not bony) part of the roof of the mouth.

Refers to muscle, fat, fibrous tissue, blood vessels, or other supporting tissue of the body.

A specialist who evaluates and treats people with communication and swallowing problems. Also called speech pathologist.

Flat cell that looks like a fish scale under a microscope. These cells cover inside and outside surfaces of the body. They are found in the tissues that form the surface of the skin, the lining of the hollow organs of the body (such as the bladder, kidney, and uterus), and the passages of the respiratory and digestive tracts.

A cell from which other types of cells develop. For example, blood cells develop from blood-forming stem cells.

A method of replacing immature blood-forming cells that were destroyed by cancer treatment. The stem cells are given to the person after treatment to help the bone marrow recover and continue producing healthy blood cells.

Unable to produce children. Also means free from germs.

A type of drug used to relieve swelling and inflammation. Some steroid drugs may also have antitumor effects.

Inflammation or irritation of the mucous membranes in the mouth.

The response of the body to physical, mental, or emotional pressure. This may make a person feel frustrated, angry, or anxious, and may cause unhealthy chemical changes in the body. Untreated, long-term stress may lead to many types of mental and physical health problems.

Adding nutrients to the diet.

Care given to improve the quality of life of patients who have a serious or life-threatening disease. The goal of supportive care is to prevent or treat as early as possible the symptoms of a disease, side effects caused by treatment of a disease, and psychological, social, and spiritual problems related to a disease or its treatment. Also called comfort care, palliative care, and symptom management.

A procedure to remove or repair a part of the body or to find out whether disease is present. An operation.

An indication that a person has a condition or disease. Some examples of symptoms are headache, fever, fatigue, nausea, vomiting, and pain.

Treatment.

A group or layer of cells that work together to perform a specific function.

A plant with leaves that have high levels of the addictive chemical nicotine. The leaves may be smoked (in cigarettes, cigars, and pipes), applied to the gums (as dipping and chewing tobacco), or inhaled (as snuff). Tobacco leaves also contain many cancer-causing chemicals, and tobacco use and exposure to secondhand tobacco smoke have been linked to many types of cancer and other diseases. The scientific name is Nicotiana tabacum.

On the surface of the body.

A surgical procedure in which tissue or an organ is transferred from one area of a person’s body to another area, or from one person (the donor) to another person (the recipient).

A type of enteral nutrition (nutrition that is delivered into the digestive system in a liquid form). For tubefeeding, a small tube may be placed through the nose into the stomach or the small intestine. Sometimes it is surgically placed into the stomach or the intestinal tract through an opening made on the outside of the abdomen, depending on how long it will be used. People who are unable to meet their needs with food and beverages alone, and who do not have vomiting or uncontrollable diarrhea may be given tubefeedings. Tubefeeding can be used to add to what a person is able to eat or can be the only source of nutrition.

An abnormal mass of tissue that results when cells divide more than they should or do not die when they should. Tumors may be benign (not cancerous), or malignant (cancerous). Also called neoplasm.

A break on the skin, in the lining of an organ, or on the surface of a tissue. An ulcer forms when the surface cells become inflamed, die, and are shed. Ulcers may be linked to cancer and other diseases.

The formation of a break on the skin or on the surface of an organ. An ulcer forms when the surface cells die and are cast off. Ulcers may be associated with cancer and other diseases.

Invisible rays that are part of the energy that comes from the sun. Ultraviolet radiation also comes from sun lamps and tanning beds. It can damage the skin and cause melanoma and other types of skin cancer. Ultraviolet radiation that reaches the Earth's surface is made up of two types of rays, called UVA and UVB rays. UVB rays are more likely than UVA rays to cause sunburn, but UVA rays pass deeper into the skin. Scientists have long thought that UVB radiation can cause melanoma and other types of skin cancer. They now think that UVA radiation also may add to skin damage that can lead to skin cancer and cause premature aging. For this reason, skin specialists recommend that people use sunscreens that reflect, absorb, or scatter both kinds of ultraviolet radiation. Also called UV radiation.

Having to do with a virus.

In medicine, a very simple microorganism that infects cells and may cause disease. Because viruses can multiply only inside infected cells, they are not considered to be alive.

A nutrient that the body needs in small amounts to function and stay healthy. Sources of vitamins are plant and animal food products and dietary supplements. Some vitamins are made in the human body from food products. Vitamins are either fat-soluble (can dissolve in fats and oils) or water-soluble (can dissolve in water). Excess fat-soluble vitamins are stored in the body’s fatty tissue, but excess water-soluble vitamins are removed in the urine. Examples are vitamin A, vitamin C, and vitamin E.

To eject some or all of the contents of the stomach through the mouth.

Refers to a blood cell that does not contain hemoglobin. White blood cells include lymphocytes, neutrophils, eosinophils, macrophages, and mast cells. These cells are made by bone marrow and help the body fight infections and other diseases. Also called WBC.

A break in the skin or other body tissues caused by injury or surgical incision (cut).

A type of high-energy radiation. In low doses, x-rays are used to diagnose diseases by making pictures of the inside of the body. In high doses, x-rays are used to treat cancer.

Dry mouth. It occurs when the body is not able to make enough saliva.

A substance required for cell growth and tissue repair. It is being studied as a way to prevent or decrease mucositis caused by radiation therapy.