Chemotherapy and radiation may damage the cells lining the mouth, throat, and gastrointestinal (GI) tract. This side effect of cancer treatment, called mucositis, produces mouth sores and throat discomfort. It can significantly affect your quality of life and may cause delays in treatment.
Treatment for mucositis usually consists of supportive therapies, such as mouthwashes. These are intended to reduce soreness until the cells in the GI tract (including the mouth) regenerate themselves. This takes about 7 to 14 days.
A new biologic therapy may offer better results. Called Kepivance™ (palifermin), a recombinant form of human keratinocyte growth factor, it appears to reduce mouth and throat soreness and improve function by stimulating the cells that protect the lining of the mouth and GI tract.
What causes mouth sores?
Chemotherapy and radiation kill rapidly dividing cells, such as cancer cells. However, the lining of the GI tract, including the mouth and the throat, is also made up of cells that divide rapidly. For this reason, the GI tract is particularly susceptible to damage by chemotherapy and radiation treatment.
What are the signs and symptoms of mouth sores?
Mouth sores commonly occur 3 to 10 days after your treatment with chemotherapy. You may experience a burning sensation followed by ulcers, and your mouth may appear red (inflammation) with sores (ulcerations). There may be associated discomfort and pain.
Mouth sores can make chewing and swallowing difficult, interfering with your nutrition and food intake and leading to weight loss. Your speech may also be affected because of the soreness. Mouth sores may make you more susceptible to bacterial, fungal, or viral infections in the mouth. Ultimately, mouth sores can become severe enough that your dosage must be reduced or your treatment delayed to allow your mouth to heal.
Although mouth sores can occur with any treatment for cancer, mucositis is more severe if you are treated with the following:
- Stem cell transplants
- Radiation for head and neck cancer
- Combined chemotherapy and radiation therapy
- High-dose treatment
- Frequent dosing schedules, such as weekly chemotherapy
The technique used to administer radiation may also affect the severity and duration of mouth sores. The following radiation techniques tend to produce less severe side effects:
- Hyperfractionated radiation involves lower doses administered more frequently, resulting in less severe side effects.
- Intensity-modulated radiation therapy (IMRT) spares normal tissue, reducing mouth sores, while still delivering the full radiation dose or even an increased dose to the cancer.
What makes mouth sores worse?
A number of factors contribute to the severity of mouth sores, including:
- Poor oral and dental health before treatment
- Kidney disease
- Being young or old
- Smoking and the use of chewing tobacco during episodes of mucositis
- Harsh foods and alcohol
- Other disease, such as diabetes or AIDS
How are mouth sores treated?
Until recently, the only approaches to managing oral mucositis included good oral care, mouthwashes, cryotherapy (sucking on ice chips) to minimize the damage from chemotherapy drugs, Salagen® (pilocarpine HCI), a drug that stimulates salivary flow, and other investigational treatments. A promising new approach to the prevention and treatment of mouth sores is the use of growth factors. Growth factors are natural substances produced by the body to stimulate cell growth. The new drug palifermin is a growth factor produced in a laboratory and is designed to protect the cells in the mouth and GI tract from mucositis.
Oral care - Good oral care, defined as frequently rinsing the mouth with saline and brushing the teeth two to three times per day, may help prevent mouth sores.
Mouthwashes - Salt and baking soda mouthwash has been shown to relieve mouth sores as well as medicated mouthwashes, and is less expensive. In fact, some researchers suggest that rinsing with chlorhexidine, an antimicrobial drug used to treat gum disease, did not provide a benefit and actually increased the risk of mouth sores in chemotherapy patients.
Rinsing with a mouthwash containing the ulcer drug sucralfate has produced varied results in the treatment of mouth sores. Sucralfate has been shown to reduce mouth sores, but other researchers have found salt and baking soda to be equally effective.
Cryotherapy (ice chips) - Sucking ice chips when the chemotherapy drug is most concentrated in the body can relieve mouth pain. This technique, called cryotherapy, works by decreasing blood flow to the cells in the mouth, reducing exposure to the drug, and decreasing the risk of developing mouth sores. According to a recent Cochrane review, sucking ice is the only measure proven to prevent mouth sores.
Palifermin (keratinocyte growth factor) - Keratinocyte growth factor is a naturally produced substance that stimulates the growth of cells involved in protecting the lining of the mouth. Palifermin is produced in a laboratory and is designed to mimic natural keratinocyte growth factor. By stimulating growth in the cells that line the mouth and GI tract, palifermin may help to reduce mucositis.
Palifermin is the first FDA-approved drug for the prevention and treatment of mucositis. In clinical trials, palifermin has demonstrated the ability to protect the epithelial cells from the damaging effects of radiation and chemotherapy in patients undergoing autologous stem cell transplantation. Research is under way to determine whether palifermin may benefit other patients.
Ethyol® (amifostine) - Amifostine is a drug that protects against the damage of radiation and is the first drug to be approved by the FDA for the treatment of patients receiving radiation therapy for head and neck cancers. Clinical trials have demonstrated that amifostine can reduce dry mouth and may prevent mouth sores; however, more research is needed to prove the effect of this drug on mouth sores.