MouthMade

What causes oral mucositis?

Chemotherapy and radiation work by preventing the growth of new cancer cells by killing cancer cells that are already there. Unfortunately, these treatments can’t tell the difference between healthy cells and cancer cells. The side effects of therapy, including oral mucositis (OM), happen when healthy cells are also killed. The combination of chemotherapy and radiation increases the risk of developing severe oral mucositis. The symptoms of oral mucositis also tend to get worse the longer radiation treatment lasts.

During radiation for head and neck cancer or conditioning regimen for Bone Marrow Transplant [BMT] or Hematopietic Stem Cell Transplantation (HSCT), the beam of radiation passes near and through the mouth. Normally healthy cells in the mouth quickly divide and replace surface cells with new cells. However radiation kills these dividing cells meaning the surface cells cannot be replaced, causing ulcers to form.

Radiation to the head and neck and chemotherapy damage the glands in the mouth that produce saliva (spit), causing the mouth to be drier than normal. A dry mouth means that there is less saliva which makes it difficult to chew and swallow.  Dry mouth is also more likely to be damaged by hard food that is normally washed away by saliva.

The type of chemotherapy used to treat the cancer will affect the likelihood of developing oral mucositis. There are many types of chemotherapy that are known to cause oral mucositis. Some of these therapies are listed below:

• 5-fluorouracil
• Methotrexate
• Doxorubicin (Adriamycin®)
• Etoposide (Vepesid®)
• Melphalan
• Cyclophosphamide
• Capecitabine (Xeloda®)
• Docetaxel (Taxotere®)
• Cisplatin

All radiation that passes through and near the mouth is very likely to cause oral mucositis.

Speak to your doctor or nurse if you are worried about oral mucositis.

Download an oral mucositis patient factsheet for your own information and a nurse factsheet to give to your nurse.

1. Pico J-L et al. The Oncologist 1998;3(6):446–451.