Overview

Oral mucositis (OM) is a debilitating inflammatory condition of the oral mucosa. It occurs due to radiation, chemotherapy, and stem cell transplantation. It is a painful side effect of cancer treatments characterized by ulceration, redness, and oedema of the epithelial oral mucosa. 

About 90% of head and neck cancer patients treated with chemotherapy and radiation therapy develop oral mucositis. Severe cases of oral mucositis require hospitalization for high-grade mucositis management. The severe pain can necessitate the need for parenteral nutrition. It can interrupt the ongoing cancer treatment, leading to a reduction in quality of life and sometimes to poor cancer prognosis due to the delay in treatment, and an increased overall treatment cost.¹

Causes and risk factors

Mucositis follows cancer treatments like chemotherapy, radiation therapy, and stem cell transplants. These treatments attack cells that rapidly divide, including the oral mucosa. Cancer therapy does not differentiate between tumour cells and normal cells. The mucosa has high and rapid turnover levels making it perfect to play the protective mucus membrane barrier to our entire digestive system from our mouths through our intestines.

Unfortunately, cancer treatment damages their ability to replicate and heal, exposing parts of our bodies the mucosa was covering before it got eroded, leading to severe pain and susceptibility to infection. Oral mucositis commonly affects the inner lining of the cheeks (buccal mucosa), soft palate, floor of the mouth, tongue, and lips.²

If you are receiving cancer treatment you may have a higher risk of developing oral mucositis if you have the following:

• Smoke or chew tobacco
• Consume large amounts of alcohol
• Have a low body mass index (BMI)
• Dehydration
• Protein deficiency
• Dental implants or dentures
• Gum disease, kidney disease, diabetes or HIV
• Poor oral hygiene

Signs and symptoms of oral mucositis

Symptoms of oral mucositis starts usually one week after chemotherapy, and two weeks after radiotherapy and can include the following: 

• Painful mouth ulcers and sore gums  
• The inflammation causes red, swollen, shiny mouth and gums
• Dry mouth
• Thick saliva
• The white mucous coat covering the oral mucosa
• Bleeding 
• In severe cases bus discharge and difficulty in swallowing and talking

Diagnosis of oral mucositis

Oral mucositis is diagnosed on medical history and clinical examinations. The fact that the patient is currently undergoing chemotherapy, radiotherapy, or stem cell transplantation and co-existing with risk factors is enough to diagnose oral mucositis. A sample for laboratory investigations is only required if there is a secondary infection, to rule out any viral or fungal infection.

Different grading scales have been developed to determine the severity of oral mucositis including the World Health Organization (WHO) scale and the National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events (CTCAE).⁴

World health organization (WHO)

The World Health Organization (WHO) scale combines subjective and objective oral mucositis measures.

Grade 0 = No oral mucositis

Grade 1 = Erythema and soreness

Grade 2 = Ulcers and erythema, but a solid diet is tolerated

Grade 3 = Ulcers due to mucositis requiring a liquid diet

Grade 4 = Ulcers, solid and liquid diets are both not well tolerated

The national cancer institute (NCI) Common terminology criteria for adverse events (CTCAE)

The CTCAE scale is divided into two parts: a clinical exam and a symptoms-based exam. And is rated from 1 to 5.

Functional/symptoms-based exam

Grade 1 = Asymptomatic or mild symptoms, intervention is not indicated.

Grade 2 = Moderate pain or ulcer that does not interfere with oral intake, but the patient requires a modified diet.

Grade 3 = Severe pain which interferes with oral intake

Grade 4 = Life-threatening consequences that require urgent intervention

Grade 5 = Death

Clinical exam

Grade 1 = erythema

Grade 2 = patchy ulceration or pseudo membranes

Grade 3 = Minor trauma resulting in bleeding, ulcers, or pseudo membranes

Grade 4 = Tissue necrosis, spontaneous bleeding, life-threatening events

Grade 5 = Death

Management and treatment of oral mucositis

There are different recommended treatment/management strategies suggested by scientists and oral care providers for oral mucositis including the following:^{4 5}

• Prehabilitation and basic oral care: Adequate oral care and proper hygiene can minimize OM complications and prevent secondary infections. Use a soft brush, dental floss, and unmedicated mouth rinses like saline, sodium bicarbonate, or a combination of both. It is also recommended to do a mechanical cleaning of teeth and assess the status of oral tissues before the beginning of cancer treatment
• Tobacco and alcohol cessation: stopping smoking, tobacco use, and alcohol consumption is advised before starting the treatment
• Anti-inflammatory agents: Benzylamine hydrochloride mouthwash is recommended for preventing oral mucositis for head and neck cancer patients receiving a moderate dose of radiation therapy or chemotherapy-radiotherapy (CT-RT)
• Hydration of the oral mucosa: Adequate lubrication, maintaining hydration of mucosa, and avoiding all irritants are essential to prevent and manage OM. Topical barrier gels are available to hydrate oral mucosal surfaces
• Pain management: Topical morphine mouthwash of 0.2% is usually recommended to reduce the pain for patients receiving radiotherapy and chemotherapy. There are other mouth rinses for managing the pain including the magic mouthwash. It contains an anaesthetic, antacid, and diphenhydramine and may have steroid
• Low-level laser therapy (LLLT): LLLT induces a biological reaction photobiomodulation. It promotes the regeneration response of tissues affected by mucositis and prevents inflammation.
• Cryotherapy: Cryotherapy is placing a source of cold in the oral cavity to induce vasoconstriction that reduces the absorption of cytotoxic agents into the oral mucosa and prevents the occurrence of oral mucositis. The cooling process is temporary; therefore, it is recommended with chemotherapeutic agents with a shorter half-life
• Chemoprotective agents:  Palifermin, a keratinocyte growth factor, is recommended for severe cases of oral mucositis associated with autologous hematopoietic stem cell transplant regimens. It decreases the incidence, severity, and duration of OM

Summary

Oral mucositis is a painful inflammation and ulceration of the mucous membranes in the mouth, often occurring as a side effect of chemotherapy or radiation therapy, particularly in cancer treatments. It results from the damage these therapies cause to the rapidly dividing cells of the oral lining, leading to sores, redness, and difficulty eating, drinking, or speaking.

Oral mucositis is primarily diagnosed by visual examination of the mouth. The severity is graded using standardized scales, such as the World Health Organization (WHO) or the National Cancer Institute (NCI) scales, to assess the extent of ulceration and its impact on oral function.

Treatment focuses on symptom relief and promoting healing. Pain management is key and may include topical anaesthetics, analgesics, and mouth rinses. Oral hygiene is critical, use soft toothbrushes and non-irritating mouthwashes. In severe cases, nutritional support, such as feeding tubes, may be necessary. Preventive measures include cryotherapy (ice chips), low-level laser therapy, and agents like palifermin, which stimulate mucosal healing.

Effective management of oral mucositis improves patient comfort, reduces the risk of infection, and continues cancer therapy, making it a crucial aspect of supportive care in oncology.