Complications are new medical problems that occur during or after a disease, procedure, or treatment and that make recovery harder. The complications may be side effects of the disease or treatment, or they may have other causes. Oral complications affect the mouth.
Cancer patients have a high risk of oral complications for a number of reasons:
These cancer treatments slow or stop the growth of fast growing cells, such as cancer cells. Normal cells in the lining of the mouth also grow quickly, so anticancer treatment can stop them from growing, too. This slows down the ability of oral tissue to repair itself by making new cells.
There are many different kinds of bacteria in the mouth. Some are helpful and some are harmful. Chemotherapy and radiation therapy may cause changes in the lining of the mouth and the salivary glands, which make saliva. This can upset the healthy balance of bacteria. These changes may lead to mouth sores, infections, and tooth decay.
This summary is about oral complications caused by chemotherapy and radiation therapy.
Sometimes treatment doses need to be decreased or treatment stopped because of oral complications. Preventive care before cancer treatment begins and treating problems as soon as they appear may make oral complications less severe. When there are fewer complications, cancer treatment may work better and you may have a better quality of life.
To manage oral complications, the oncologist will work closely with your dentist and may refer you to other health professionals with special training. These may include the following specialists:
The goals of oral and dental care are different before, during, and after cancer treatment:
The most common oral complications from cancer treatment include the following:
These complications can lead to other problems such as dehydration and malnutrition.
Oral complications caused by chemotherapy include the following:
Oral complications caused by radiation therapy to the head and neck include the following:
The most common oral complications may be caused by either chemotherapy or radiation therapy. These include the following:
Radiation therapy can directly damage oral tissue, salivary glands, and bone. Areas treated may scar or waste away. Total-body radiation can cause permanent damage to the salivary glands. This can change the way foods taste and cause dry mouth.
Slow healing and infection are indirect complications of cancer treatment. Both chemotherapy and radiation therapy can stop cells from dividing and slow the healing process in the mouth. Chemotherapy may decrease the number of white blood cells and weaken the immune system (the organs and cells that fight infection and disease). This makes it easier to get an infection.
Acute complications are ones that occur during treatment and then go away. Chemotherapy usually causes acute complications that heal after treatment ends.
Chronic complications are ones that continue or appear months to years after treatment ends. Radiation can cause acute complications but may also cause permanent tissue damage that puts you at a lifelong risk of oral complications. The following chronic complications may continue after radiation therapy to the head or neck has ended:
Oral surgery or other dental work can cause problems in patients who have had radiation therapy to the head or neck. Make sure that your dentist knows your health history and the cancer treatments you received.
Problems such as cavities, broken teeth, loose crowns or fillings, and gum disease can get worse or cause problems during cancer treatment. Bacteria live in the mouth and may cause an infection when the immune system is not working well or when white blood cell counts are low. If dental problems are treated before cancer treatments begin, there may be fewer or milder oral complications.
Ways to prevent oral complications include the following:
Your dentist should be part of your cancer care team. It is important to choose a dentist who has experience treating patients with oral complications of cancer treatment. A checkup of your oral health at least a month before cancer treatment begins usually allows enough time for the mouth to heal if any dental work is needed. The dentist will treat teeth that have a risk of infection or decay. This will help avoid the need for dental treatments during cancer treatment. Preventive care may help lessen dry mouth, which is a common complication of radiation therapy to the head or neck.
A preventive oral health exam will check for the following:
The goal of the oral care plan is to find and treat oral disease that may cause complications during treatment and to continue oral care during treatment and recovery. Different oral complications may occur during the different phases of a transplant. Steps can be taken ahead of time to prevent or lessen how severe these side effects will be.
Oral care during radiation therapy will depend on the following:
Continuing to smoke tobacco may slow down recovery. It can also increase the risk that the head or neck cancer will recur or that a second cancer will form.
It is important to keep a close watch on oral health during cancer treatment. This helps prevent, find, and treat complications as soon as possible. Keeping the mouth, teeth, and gums clean during and after cancer treatment may help decrease complications such as cavities, mouth sores, and infections.
Everyday oral care during chemotherapy and radiation therapy includes the following:
Brushing teeth
Rinsing
Flossing
Lip care
Denture care
For special oral care during high-dose chemotherapy and stem cell transplant, see the Managing Oral Complications of High-Dose Chemotherapy and/or Stem Cell Transplant section of this summary.
The terms "oral mucositis" and "stomatitis" are often used in place of each other, but they are different.
Mucositis may be caused by either radiation therapy or chemotherapy.
Swishing ice chips in the mouth for 30 minutes, beginning 5 minutes before patients receive fluorouracil, may help prevent mucositis. Patients who receive high-dose chemotherapy and stem cell transplant may be given medicine to help prevent mucositis or keep it from lasting as long.
Mucositis may cause the following problems:
Treatment of mucositis caused by either radiation therapy or chemotherapy is about the same. Treatment depends on your white blood cell count and how severe the mucositis is. The following are ways to treat mucositis during chemotherapy, stem cell transplant, or radiation therapy:
Cleaning the mouth
Relieving mucositis pain
See the Pain section of this summary for more information on pain control.
A cancer patient's pain may come from the following:
Because there can be many causes of oral pain, a careful diagnosis is important. This may include:
Cancer can cause pain in different ways:
Oral mucositis is the most common side effect of radiation therapy and chemotherapy. Pain in the mucous membranes often continues for a while even after the mucositis is healed.
Surgery may damage bone, nerves, or tissue and may cause pain. Bisphosphonates, drugs taken to treat bone pain, sometimes cause bone to break down. This is most common after a dental procedure such as having a tooth pulled. (See the Oral Complications Not Related to Chemotherapy or Radiation Therapy section of this summary for more information.)
Patients who have transplants may develop graft-versus-host-disease (GVHD). This can cause inflammation of the mucous membranes and joint pain. (See the Managing Oral Complications of High-Dose Chemotherapy and/or Stem Cell Transplant section of this summary for more information).
If an anticancer drug is causing 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 a medical history, physical and dental exams, and x-rays of the teeth.
Some patients may have sensitive teeth weeks or months after chemotherapy has ended. Fluoride treatments or toothpaste for sensitive teeth may relieve the discomfort.
Pain in the teeth or jaw muscles may occur in patients who grind their teeth or clench their jaws, often because of stress or not being able to sleep. Treatment may include muscle relaxers, drugs to treat anxiety, physical therapy (moist heat, massage, and stretching), and mouth guards to wear while sleeping.
Oral and facial pain can affect eating, talking, and many other activities that involve the head, neck, mouth, and throat. Most patients with head and neck cancers have pain. The doctor may ask the patient to rate the pain using a rating system. This may be on a scale from 0 to 10, with 10 being the worst. The level of pain felt is affected by many different things. It's important for patients to talk with their doctors about pain.
Pain that is not controlled can affect all areas of the patient's life. Pain may cause feelings of anxiety and depression, and may prevent the patient from working or enjoying everyday life with friends and family. Pain may also slow the recovery from cancer or lead to new physical problems. Controlling cancer pain can help the patient enjoy normal routines and a better quality of life.
For oral mucositis pain, topical treatments are usually used. See the Oral Mucositis section of this summary for information on relieving oral mucositis pain.
Other pain medicines may be also be used. Sometimes, more than one pain medicine is needed. Muscle relaxers and medicines for anxiety or depression or to prevent seizures may help some patients. For severe pain, opioids may be prescribed.
Non-drug treatments may also help, including the following:
Oral mucositis breaks down the lining of the mouth, which lets bacteria and viruses get into the blood. When the immune system is weakened by chemotherapy, even good bacteria in the mouth can cause infections. Germs picked up from the hospital or other places may also cause infections.
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 have a higher risk of serious infections. Dry mouth, which is common during radiation therapy to the head and neck, may also raise the risk of infections in the mouth.
Dental care given before chemotherapy and radiation therapy are started can lower the risk of infections in the mouth, teeth, or gums.
Bacterial infections
Treatment of bacterial infections in patients who have gum disease and receive high-dose chemotherapy may include the following:
Fungal infections
The mouth normally contains fungi that can live on or in the oral cavity without causing any problems. However, an overgrowth (too much fungi) in the mouth can be serious and should be treated.
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. Also, fungal infections are common in patients treated with radiation therapy. Patients receiving cancer treatment may be given drugs to help prevent fungal infections from occurring.
Candidiasis is a type of fungal infection that is common in patients receiving both chemotherapy and radiation therapy. Symptoms may include a burning pain and taste changes. Treatment of fungal infections in the lining of the mouth only may include mouthwashes and lozenges that contain antifungal drugs. An antifungal rinse should be used to soak dentures and dental devices and to rinse the mouth. Drugs may be used to when rinses and lozenges do not get rid of the fungal infection. Drugs are sometimes used to prevent fungal infections.
Viral infections
Patients receiving chemotherapy, especially those with immune systems weakened by stem cell transplant, have an increased risk of viral infections. Herpesvirus infections and other viruses that are latent (present in the body but not active or causing symptoms) may flare up. Finding and treating the infections early is important. Giving antiviral drugs before treatment starts can lower the risk of viral infections.
High-dose chemotherapy and stem cell transplants can cause a lower-than-normal number of platelets in the blood. This can cause problems with the body's blood clotting process. Bleeding may be mild (small red spots on the lips, soft palate, or bottom of the mouth) or severe, especially at the gum line and from ulcers in the mouth. Areas of gum disease may bleed on their own or when irritated by eating, brushing, or flossing. When platelet counts are very low, blood may ooze from the gums.
Continuing regular oral care will help prevent infections that can make bleeding problems worse. Your dentist or medical doctor can explain how to treat bleeding and safely keep your mouth clean when platelet counts are low.
Treatment for bleeding during chemotherapy may include the following:
Saliva is made by salivary glands. Saliva is needed for taste, swallowing, and speech. It helps prevent infection and tooth decay by cleaning off the teeth and gums and preventing too much acid in the mouth.
Radiation therapy can damage salivary glands and cause them to make too little saliva. Some types of chemotherapy used for stem cell transplant may also damage salivary glands.
When there is not enough saliva, the mouth gets dry and uncomfortable. This condition is called dry mouth (xerostomia). The risk of tooth decay, gum disease, and infection increases, and your quality of life suffers.
Symptoms of dry mouth include the following:
Dry mouth caused by chemotherapy for stem cell transplant is usually temporary. The salivary glands often recover 2 to 3 months after chemotherapy ends.
The amount of saliva made by the salivary glands usually starts to decrease within 1 week after starting radiation therapy to the head or neck. It continues to decrease as treatment goes on. How severe the dryness is depends on the dose of radiation and the number of salivary glands that receive radiation.
Salivary glands may partly recover during the first year after radiation therapy. However, recovery is usually not complete, especially if the salivary glands received direct radiation. Salivary glands that did not receive radiation may start making more saliva to make up for the loss of saliva from the damaged glands.
Care of dry mouth may include the following:
A dentist may give the following treatments:
Acupuncture may also help relieve dry mouth.
Dry mouth and changes in the balance of bacteria in the mouth increase the risk of tooth decay (cavities). Careful oral hygiene and regular care by a dentist can help prevent cavities. See the Regular Oral Care section of this summary for more information.
Changes in the sense of taste is a common side effect of both chemotherapy and head or neck radiation therapy. Taste changes can be caused by damage to the taste buds, dry mouth, infection, or dental problems. Foods may seem to have no taste or may not taste the way they did before cancer treatment. Radiation may cause a change in sweet, sour, bitter, and salty tastes. Chemotherapy drugs may cause an unpleasant taste.
In most patients receiving chemotherapy and in some patients receiving radiation therapy, taste returns to normal a few months after treatment ends. However, for many radiation therapy patients, the change is permanent. In others, the taste buds may recover 6 to 8 weeks or more after radiation therapy ends. Zinc sulfate supplements may help some patients recover their sense of taste.
Cancer patients who are receiving high-dose chemotherapy or radiation therapy often feel fatigue (a lack of energy). This can be caused by either the cancer or its treatment. Some patients may have problems sleeping. Patients may feel too tired for regular oral care, which may further increase the risk for mouth ulcers, infection, and pain. For more information, see Cancer Fatigue.
Patients treated for head and neck cancers have a high risk of malnutrition. The cancer itself, poor diet before diagnosis, and complications from surgery, radiation therapy, and chemotherapy can lead to nutrition problems. Patients may lose the desire to eat because of 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 may help patients with cancer meet their nutrition needs:
Meeting with a nutrition counselor may help during and after treatment.
Many patients treated for head and neck cancers who receive radiation therapy only are able to eat soft foods. As treatment continues, most patients will add or switch to high-calorie, high-protein liquids to meet their nutrition needs. Some patients may need to receive the liquids through a tube that is inserted into the stomach or small intestine. Almost all patients who receive chemotherapy and head or neck radiation therapy at the same time will need tube feedings within 3 to 4 weeks. Studies show that patients do better if they begin these feedings at the start of treatment, before weight loss occurs.
Normal eating by mouth can begin again when treatment is finished and the area that received radiation is healed. A team that includes a speech and swallowing therapist can help the patients with the return to normal eating. Tube feedings are decreased as eating by mouth increases, and are stopped when you are able to get enough nutrients by mouth. Although most patients will once again be able to eat solid foods, many will have lasting complications such as taste changes, dry mouth, and trouble swallowing.
Treatment for head and neck cancers may affect the ability to move the jaws, mouth, neck, and tongue. There may be problems with swallowing. Stiffness may be caused by:
Jaw stiffness may lead to serious health problems, including:
The risk of having jaw stiffness from radiation therapy increases with higher doses of radiation and with repeated radiation treatments. The stiffness usually begins around the time the radiation treatments end. It may get worse over time, stay the same, or get somewhat better on its own. Treatment should begin as soon as possible to keep the condition from getting worse or becoming permanent. Treatment may include the following
Swallowing problems are common in patients who have head and neck cancers. Cancer treatment side effects such as oral mucositis, dry mouth, skin damage from radiation, infections, and graft-versus-host-disease (GVHD) may all cause problems with swallowing.
Other complications can develop from being unable to swallow and these can further decrease the patient's quality of life:
The following may affect the risk of swallowing problems after radiation therapy:
Some side effects go away within 3 months after the end of treatment, and patients are able to swallow normally again. However, some treatments can cause permanent damage or late effects. Late effects are health problems that occur long after treatment has ended. Conditions that may cause permanent swallowing problems or late effects include:
The oncologist works with other health care experts who specialize in treating head and neck cancers and the oral complications of cancer treatment. These specialists may include the following:
Radiation therapy can destroy very small blood vessels within the bone. This can kill bone tissue and lead to bone fractures or infection. Radiation can also kill tissue in the mouth. Ulcers may form, grow, and cause pain, loss of feeling, or infection.
Preventive care can make tissue and bone loss less severe.
The following may help prevent and treat tissue and bone loss:
For more information about managing mouth sores, dry mouth, and taste changes, see Nutrition During Cancer Treatment.
Graft-versus-host disease (GVHD) occurs when your tissue reacts to bone marrow or stem cells that come from a donor. Symptoms of oral GVHD include the following:
It's important to have these symptoms treated because they can lead to weight loss or malnutrition. Treatment of oral GVHD may include the following:
The following can help in the care and use of dentures, braces, and other oral devices during high-dose chemotherapy or stem cell transplant:
Talk to your medical doctor or dentist about the best way to take care of your mouth during high-dose chemotherapy and stem cell transplant. Careful brushing and flossing may help prevent infection of oral tissues. The following may help prevent infection and relieve discomfort of oral in tissues:
Medicines may be given to help prevent mouth sores or help the mouth heal faster if it is damaged by chemotherapy or radiation therapy. Also, holding ice chips in the mouth during high-dose chemotherapy, may help prevent mouth sores.
Regular dental treatments, including cleaning and polishing, should wait until the transplant patient's immune system returns to normal. The immune system can take 6 to 12 months to recover after high-dose chemotherapy and stem cell transplant. During this time, the risk of oral complications is high. If dental treatments are needed, antibiotics and supportive care are given.
Supportive care before oral procedures may include giving antibiotics or immunoglobulin G, adjusting steroid doses, and/or platelet transfusion.
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 oral cancer in transplant patients. The lips and tongue are the areas that are affected most often.
Second cancers are more common in patients treated for leukemia or lymphoma, Multiple myeloma patients who received a stem cell transplant using their own stem cells sometimes develop an oral plasmacytoma.
Patients who received a transplant should see a doctor if they have swollen lymph nodes or lumps in soft tissue areas. This could be a sign of a second cancer.
Some drugs break down bone tissue in the mouth. This is called osteonecrosis of the jaw (ONJ). ONJ can also cause infection. Symptoms include pain and inflamed lesions in the mouth, where areas of damaged bone may show.
Drugs that may cause ONJ include the following:
It's important for the health care team to know if a patient has been treated with these drugs. Cancer that has spread to the jawbone can look like ONJ. A biopsy may be needed to find out the cause of the ONJ.
ONJ is not a common condition. It occurs more often in patients who receive bisphosphonates or denosumab by injection than in patients who take them by mouth. Taking bisphosphonates, denosumab, or angiogenesis inhibitors increases the risk of ONJ. The risk of ONJ is much greater when angiogenesis inhibitors and bisphosphonates are used together.
The following may also increase the risk of ONJ:
Patients with bone metastases may decrease their risk of ONJ by getting screened and treated for dental problems before bisphosphonate or denosumab therapy is started.
Treatment of ONJ may include the following:
During treatment for ONJ, you should continue to brush and floss after meals to keep your mouth very clean. It is best to avoid tobacco use while ONJ is healing.
You and your doctor can decide whether you should stop using medicines that cause ONJ, based on the effect it would have on your general health.
The social problems related to oral complications can be the hardest problems for cancer patients to cope with. Oral complications affect eating and speaking and may make you 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 cannot be used because they can make oral complications worse. See the following PDQ summaries for more information:
Education, supportive care, and the treatment of symptoms are important for patients who have mouth problems that are related to cancer treatment. Patients are watched closely 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.
Children who received high-dose chemotherapy or radiation therapy to the head and neck may not have normal dental growth and development. New teeth may appear late or not at all, and tooth size may be smaller than normal. The head and face may not develop fully. The changes are usually the same on both sides of the head and are not always noticeable.
Orthodontic treatment for patients with these dental growth and development side effects is being studied.
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