Radiation therapy for small intestine cancer

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Radiation therapy uses high-energy rays or particles to destroy cancer cells.

Radiation therapy is sometimes used to treat small intestine adenocarcinoma. Your healthcare team will use what they know about the cancer and about your health to plan the type and amount of radiation, and when and how it is given.

Radiation therapy is most often used to relieve pain or control the symptoms of advanced small intestine adenocarcinoma (called palliative therapy). It can be used to stop bleeding caused by the tumour and relieve pain and pressure on surrounding tissues. It can also be used to treat pain where the cancer has spread (metastasized), such as to the bones.

You may have radiation therapy to shrink a tumour before surgery. Radiation therapy and chemotherapy may be given together to treat small intestine adenocarcinoma. This is called chemoradiation.

Radiation therapy is also sometimes used to destroy cancer cells left behind after surgery to reduce the risk that the cancer will come back (recur). This is called adjuvant therapy. Researchers are still trying to find out how helpful adjuvant radiation is for people with small intestine adenocarcinoma.

External radiation therapy

External radiation therapy is most commonly used to treat small intestine adenocarcinoma.

During external radiation therapy, a machine directs radiation through the skin to the tumour and some of the tissue around it. External radiation therapy is also called external beam radiation therapy.

Doctors may use the following types of external radiation therapy to accurately target the cancer and spare as much surrounding normal tissue as possible:

  • 3D conformal radiation therapy (3D-CRT)
  • intensity-modulated radiation therapy (IMRT)
  • image-guided radiation therapy (IGRT)

Find out more about these types of external radiation therapy.

Side effects

During radiation therapy, your healthcare team protects healthy cells in the treatment area as much as possible. Side effects of radiation therapy will depend mainly on the size of the area being treated, the specific area or organs being treated, the total dose of radiation and the treatment schedule. Tell your healthcare team if you have side effects that you think are from radiation therapy. The sooner you tell them of any problems, the sooner they can suggest ways to help you deal with them.

These are common side effects of radiation therapy for small intestine adenocarcinoma:

Find out more about radiation therapy

Find out more about radiation therapy and side effects of radiation therapy. To make the decisions that are right for you, ask your healthcare team questions about radiation therapy.

Expert review and references

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