Mucositis occurs when cancer treatments break down the rapidly divided epithelial cells lining the gastro-intestinal tract (which goes from the mouth to the anus), leaving the mucosal tissue open to ulceration and infection.  Mucosal tissue, also known as mucosa or the mucous membrane, lines all body passages that communicate with the air, such as the respiratory and alimentary tracts, and have cells and associated glands that secrete mucus. The part of this lining that covers the mouth, called the oral mucosa, is one of the most sensitive parts of the body and is particularly vulnerable to chemotherapy and radiation. The oral cavity is the most common location for mucositis.

Oral mucositis is probably the most common, debilitating complication of cancer treatments, particularly chemotherapy and radiation. It can lead to several problems, including pain, nutritional problems as a result of inability to eat, and increased risk of infection due to open sores in the mucosa. It has a significant effect on the patient’s quality of life and can be dose-limiting (i.e., requiring a reduction in subsequent chemotherapy doses).

Signs of Mucositis

Signs and symptoms of mucositis include:

-Red, shiny, or swollen mouth and gums

-Blood in the mouth

-Sores in the mouth or on the gums or tongue

-Soreness or pain in the mouth or throat

-Difficulty swallowing or talking

-Feeling of dryness, mild burning, or pain when eating food

-Soft, whitish patches or pus in the mouth or on the tongue

-Increased mucus or thicker saliva in the mouth

An extreme case of the condition is called confluent mucositis.  In a worst case, the mucous membrane of the patient’s entire mouth and tongue can be coated by a white mucus coating that is up to a millimeter thick.  The combination of mucus, excess saliva and pain can make it difficult or even impossible to eat.

Who Gets Mucositis?

The majority of oral cancer patients receiving chemotherapy in combination with radiation will experience at least some degree of mucositis. When caused by chemotherapy, mucositis is usually due to the low white blood cell count; when caused by radiation, mucositis is usually due to the necrotic and inflammatory effect of radiation energy on oral mucosa.

Factors that can increase the likelihood of developing mucositis, or that can make it worse if it does occur, include:

-Poor oral or dental health.

-Smoking or chewing tobacco and drinking alcohol.

-Gender (females appear to be more likely than males to develop mucositis)


-Low body mass index.

-Diseases such as kidney disease, diabetes or HIV/AIDS.

-Previous cancer treatment.

-Chronic irritation from ill-fitting prostheses or faulty restorations can predispose patients to the development of oral mucositis due to local irritation and trauma.

-Generally, patients with hematologic malignancies have an increased rate of oral mucositis compared with those with solid tumors. This is to some extent related to the treatment regimens.

-Hyposalivation prior to and during treatment is associated with an increased risk of oral mucositis.

-The use of methotrexate for chronic GVHD prophylaxis may exacerbate lesions of oral mucositis, although this is less of a concern with newer prophylaxis regimens.

-Oral mucositis occurs independently of oral mucosal infections of viral and fungal etiology, but it may be exacerbated by such concomitant infections.

Younger patients tend to develop oral mucositis more often than older patients being treated for the same malignancy with the same regimen. This appears to be due to the more rapid rate of basal cell turnover noted in children. However, the healing of oral mucositis is also more rapid in the younger age group.

Consequences of Mucositis

It is important that cancer patients be on the lookout for signs of mucositis, which should be treated as soon as possible once diagnosed. The consequences of mucositis can be mild, requiring little intervention, but they can also be severe–such as hypovolemia, electrolyte abnormalities, and malnutrition–and even result in fatality. Oral mucositis can:

-Cause pain

-Restrict oral intake

-Act as a portal of entry for organisms

-Contribute to interruption of therapy

-Increase the use of antibiotics and narcotics

-Increase the length of hospitalization

-Increase the overall cost of treatment.

Patients with oral mucositis and neutropenia (a type of white blood cell deficiency) have a relative risk of septicemia (a systemic, toxic illness caused by the invasion of the bloodstream by virulent bacteria coming from a local infection) more than 4 times that of patients with neutropenia only.

Mucositis is further complicated by the nausea and vomiting that often occur with treatment. Chemotherapy and radiation therapy can affect the ability of cells to reproduce, slowing healing of the oral mucosa, often extending the duration of present mucositis. Patients with damaged oral mucosa and reduced immunity are also prone to mouth infections.

Taste loss tends to increase in proportion to the aggressiveness of treatment. Nausea, pain, vomiting, diarrhea, a sore or dry mouth may make eating difficult. Thus, maintaining adequate nutrition is an important challenge for oral cancer patients. Reduction of caloric intake can lead to weight loss, loss in muscle mass strength and other complications, including a decrease in immunity and a longer healing time from treatments.

Physical problems may interfere with food intake and proper nutrition. Patients with head and neck tumors may have mouth or throat pain that can interfere with chewing and compound difficulties in swallowing. Tooth and gum disease can also exacerbate issues.

Chemotherapy can inhibit appetite by the same mechanisms as radiation. This is often worsened because of accompanying nausea. Decreased food intake is common for a short period around the time of treatment. It is important to try to compensate for weight loss during this time by making a conscious effort to eat more or, if this is not possible, to use feeding tubes or food pumps.

When you experience any of these problems, first consult your physician, nurse or the registered dietitian on your health care team. With their help and with the suggestions below, you should be able to plan a diet designed to minimize these problems. Prescription medications may be required. Your dentist, dental hygienist, nurse, dietitian, and pharmacist may also be of assistance.


Oral mucositis generally begins 5-10 days following the initiation of chemotherapy and lasts anywhere from one week to six weeks or more.  Resolution (in the case of HCT) coincides with recovery of the white blood cell count, specifically when the absolute neutrophil count becomes greater than 500 cells/µL. In patients being treated for solid tumors, the duration of oral mucositis depends on the type, dose, and course of treatment.

Preventive Steps

You may not be able to stop mucositis from occurring, but there are steps you can take before beginning radiation or chemotherapy treatment to help alleviate its side effects and symptoms. The first step is to see if your doctor can recommend a dentist who deals with cancer patients.  If you wear dentures, you will need to make sure they fit properly. If any work is needed (tooth extractions