What is Oral Mucositis?

Oral mucositis is the inflammation and ulceration of the mucous membranes in the mouth. It causes redness, swelling, pain, and open sores—typically on the cheeks, lips, tongue, gums, and roof or floor of the mouth.

How Does It Occur During Cancer Therapy?

Cancer therapies like chemotherapy and radiation don’t just target cancer cells—they also damage healthy rapidly dividing cells, like those in the oral mucosa. The development of mucositis is a complex, multi-stage process:

1. Initiation (cell damage)

• Cancer treatment causes DNA damage and oxidative stress in the basal epithelial cells of the mucosa.

• This starts a chain reaction of tissue injury.

2. Upregulation and Amplification

• The body responds to injury by releasing inflammatory signals (like cytokines and TNF-alpha).

• These chemicals amplify the damage, breaking down tissue further and increasing inflammation.

3. Ulceration

• The mucosa begins to break down, leading to painful open sores.

• These ulcers can become infected with bacteria, fungi, or viruses, making the condition worse.

4. Healing (Recovery)

• After therapy ends or is paused, the body can begin rebuilding the mucosal lining.

• Healing takes time and often requires supportive care like pain relief, oral rinses, and sometimes medications that stimulate cell repair.

What Does It Feel Like?

Patients often report:

• Burning pain

• Difficulty eating, drinking, or speaking

• Increased sensitivity to hot, spicy, or acidic foods

• A feeling similar to a severe burn inside the mouth

Why It Matters

Oral mucositis isn’t just uncomfortable—it can seriously:

• Affect a patient’s quality of life

• Lead to malnutrition or dehydration

• Increase the risk of infections

• Cause delays or changes in cancer treatment