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Mouth and Throat Sores

Mouth and throat sores are a common side effect of cancer treatment in children. The clinical name for this condition is oral mucositis.

What is Oral Mucositis?

Oral refers to the mouth and throat. Mucositis is a swelling of the mucous membrane, the moist, inner lining of some body organs. Mucositis can occur anywhere along the digestive tract including the mouth, stomach, intestines, and anus. It often results in painful sores.

More than 50% of childhood cancer patients may develop mucositis. More than 75% of patients who have a hematopoietic cell transplant (also known as bone marrow transplant or stem cell transplant) will likely have this side effect. Many patients say mucositis is one of the most unpleasant side effects of cancer treatment.

Mouth and throat sores are a cause for concern because they can:

  • Cause pain and discomfort
  • Make it difficult for patients to eat and drink
  • Make patients more at risk for infection
  • Cause changes to the patient’s treatment plan

This side effect can be managed, but it may not be totally prevented. Dealing with mouth and throat sores may include:

  • Prevention
  • Treatment of pain and discomfort
  • Treatment of infections
  • Nutrition support

What Causes Mouth Sores?

The factors that make patients more likely to develop mouth and throat sores include:

  • High-dose chemotherapy
  • Hematopoietic cell transplant (also known as bone marrow transplant or stem cell transplant), related to high-dose chemotherapy before transplant
  • Radiation to the head and neck
  • Neutropenia
  • Poor dental health

Causes of Mouth Sores

Chemotherapy and radiation treatment attack rapidly dividing cancer cells. However, some healthy cells also divide rapidly, including the cells that make up the lining of the mouth, throat, and digestive tract. Chemotherapy drugs and radiation may also attack these healthy cells.

Chemotherapy drugs cause death of cells. The cells’ energy center (mitochondria) sets off a chain of events that triggers inflammation of mucous membranes of the mouth and throat.

When the cells die, the skin of the mouth breaks down.

Signs and Symptoms of Mouth and Throat Sores

Patients and families should tell the care team when signs and symptoms appear:

  • Soreness or pain in or on the lips, mouth or throat
  • Difficulty swallowing
  • Increased discharge (drooling) from inside the mouth or throat
  • White patches or sores in the mouth or throat
  • Bleeding from gums
  • Body temperature above 100.4 F or 38.0 C

Diagnosis of Mouth and Throat Sores

Mouth and throat sores are diagnosed by:

  • Physical exam of the mouth and throat. A care team member will exam the skin under the lips, inside the right and left cheek, the bottom and sides the tongue, the floor and roof of the mouth, the soft palate, and throat.
  • Patient’s report of pain and inability to eat and drink.

The care team will grade the mucositis from 1-4 based on the severity of the condition. The grade will help determine treatment methods. Grades 3-4 are considered severe -- the more severe the grade, the more likely complications will develop.

Oral Mucositis Grading

  1. Sores and redness
  2. Ulcers but able to eat
  3. Ulcers with bleeding, able to eat liquid diet only
  4. Tissue necrosis, significant bleeding, life-threatening consequences

Prevention of Mouth and Throat Sores

Mouth and throat sores cannot be prevented in some cases. But there are steps patients can take to possibly lessen the severity of the symptoms.

  • Dental exam — If possible, your child should have a dental exam before treatment begins. Make sure the dentist knows your child is a cancer patient. The exam can reveal any dental problems that may need to be corrected or monitored.
  • Oral appliances or braces may need to be removed before treatment begins.
  • Daily mouth care — Follow the care team’s instructions even if oral care is painful.
    • Brush teeth gently with a soft toothbrush. Tooth brushing must be done with care. It can cause gums to bleed and provide a portal for harmful bacteria to enter the bloodstream. Oral swabs or sponges may be an option if tooth brushing is not possible.
    • Only use mouth rinses recommended by the care team. Antibacterial rinses such as chlorhexidine can remove bacteria from the mouth.
    • Flossing may not be possible if the patient has mouth sores. Ask the care team before flossing. It can damage tissue and cause bleeding and infection.
    • A dietician will likely recommend a “soft” diet at the beginning of chemotherapy to prevent cuts in the mouth. Soft foods are also easier to chew and swallow. Patients are encouraged to avoid rough-textured food and foods that contain lots of spices or acids. They may also want to avoid very hot or cold foods.
  • The care team may encourage ways of preventing dry mouth. These methods may include drinking fluids, using a saliva substitute or mouth rinse, and consuming sugar-free candy and gum.
  • Lip care — Use lip moisturizers recommended by care team.
  • Ice therapy — Eating ice chips before and during short periods of chemotherapy may slow the development of mouth sores. This process is called cryotherapy. Cold can decrease blood flow to the mouth.
  • Palifermin — Palifermin is a medicine sometimes recommended as a preventive therapy in patients receiving autologous hematopoietic cell transplantation.

Photo modulation (low-level laser) therapy is under study as a prevention and treatment method. It uses light to promote tissue regrowth, reduce inflammation, swelling, and relieve pain.

Mouth Sore Treatment

Treatment focuses on lessening pain, treating infections, and making sure the patient gets necessary nutrition.

Pain Management

Pain treatments may be local or systemic and will depend on the patient’s symptoms.

Local treatments may include:

  • Rinses or “magic mouthwash” — The care team may recommend certain rinses or a “magic mouthwash” solution. There are many different kinds of magic mouthwash. The ingredients vary by pediatric care center. They often contain medications to soothe pain, fight infection, and reduce swelling.
  • Topical gels — Gels recommended by the care team can temporarily soothe discomfort.

Systemic treatments may include different types of pain medications. The care team may encourage other forms of pain treatment that don’t include medication.

Nutrition Support

When patients have problems eating and drinking, this situation may lead to dehydration and/or malnutrition.

In some cases, patients may need to receive nutrition through tube feeding or total parenteral nutrition (TPN).

Treatment for Infections

Mouth and throat sores provide a place for germs (bacteria, virus, fungus) to enter the body and may lead to infection.

Treatment of infection may include antibiotics, antiviral and/or antifungal agents. The care team may consult an infectious disease specialist to develop the best infection treatment plan.

Reviewed: January 2019