Radiation therapy uses high-energy radiation to kill cancer cells. Although most cases of carcinoid tumor are cured by surgery alone, radiation therapy may be an option for those who cannot undergo surgery.

External-beam radiation therapy is the type of radiation used most often for most types of gastrointestinal cancer. It is like having a regular x-ray except it takes longer and involves much higher amounts of radiation. Patients typically have treatments for 5 days a week for several weeks.

Unfortunately, radiation therapy often is not very effective against most gastrointestinal carcinoid tumors. It is used primarily to treat pain from carcinoid tumors that have spread to the bones or other parts of the body.

The main side effects of gastrointestinal radiation therapy are fatigue (tiredness), nausea, vomiting, diarrhea, and mild temporary, sunburn-like skin changes.

For more information on radiation therapy, see the American Cancer Society document, Understanding Radiation Therapy: A Guide for Patients and Families.