Stomach cancer radiation therapy is a cancer treatment that uses high energy x-rays or other types of radiation to kill cancer cells.

For purposes of this article, the term "stomach cancer" is used to refer to gastric adenocarcinoma (cancer of the glandular tissue in the stomach), which is the most common type of stomach cancer. Other types of stomach cancer include lymphomas (cancers involving the lymphatic system) and sarcomas (cancers of the connective tissue, such as muscle, fat, or blood vessels).

Stomach cancer radiation therapy is given as external or internal radiation therapy. External radiation therapy uses a machine outside of the body to send radiation toward the cancer. Internal radiation therapy uses a radioactive substance sealed in needles, seeds, wires, or catheters that are placed directly into or near the cancer. Most people go to a hospital or clinic for treatment, and treatments usually last five days a week for several weeks.

Side effects of radiation therapy will depend on the dose of radiation and the part of your body that is being treated. Radiation therapy to the abdomen may cause:

• Pain in the stomach or the intestine
• Nausea and diarrhea
• Skin to become red, dry, and tender.

Side effects from stomach cancer radiation therapy usually go away after treatment ends. Although receiving radiation therapy to treat stomach cancer may cause patients to become very tired, doctors usually advise patients to stay as active as they can.