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What to Know About Radiation Therapy for Anal Cancer

Radiation therapy is one way to treat anal cancer. This treatment is also called radiotherapy. It uses X-rays to control the growth of cancer cells. Radiation is a local treatment. That means it affects the cancer cells only in the area treated.

Getting radiation and chemotherapy together may be a better treatment for anal cancer than radiation alone.

For this treatment, you see a radiation oncologist. This doctor specializes in the use of radiation to kill cancer cells. This doctor decides how often you need radiation and at what dose.

There are two types of radiation. For external radiation, you get radiation externally from a machine outside your body. The experience is a lot like getting an X-ray, only it takes longer. It is usually given five days a week for several weeks. 

For internal radiation, the doctor places the radiation inside you. He or she places a source, such as radioactive pellets in or near the cancer.

For anal cancer, internal radiation is used much less often than external radiation. When internal radiation therapy is used, it's usually given along with external radiation therapy.

Potential side effects of radiation therapy for anal cancer

Radiation affects both normal cells and cancer cells. This means it can cause side effects. Here are some common side effects of radiation for people with anal cancer:

  • Skin irritation, itching, or burning

  • Diarrhea, sometimes with some rectal bleeding

  • Nausea and vomiting 

  • Sexual changes 

  • Urinary urgency

  • Bladder pain

  • Tiredness or fatigue


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