Anal Cancer: Radiation Therapy
What is radiation therapy?
Radiation therapy is one way to treat anal cancer. This treatment is also called radiotherapy. It uses X-rays to destroy and control the growth of cancer cells. This is a local treatment. That means it affects the cancer cells only in the area that is treated.
For this treatment, you see a radiation oncologist. This doctor specializes in the use of radiation to kill cancer cells. This doctor decides what kind of radiation you need, how often you need it, and at what dose.
How is radiation therapy used for anal cancer?
There are 2 types of radiation: External and internal.
For this type of radiation, you get the radiation from a machine outside your body. The machine doesn't touch you during the treatment. It’s a lot like getting an X-ray, but it takes longer. It’s normally given 5 days a week for several weeks.
For internal radiation, your healthcare provider 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 is used, it's often given along with external radiation therapy.
Getting radiation and chemotherapy together is a common treatment for anal cancer.
What to expect during external radiation therapy
Before you start treatment, your healthcare provider will do imaging scans of your cancer. This is done to measure the exact spot of the tumor so the beams of radiation can be focused there. Your healthcare provider may put small marks on your skin to mark the treatment area. This ensures that the radiation reaches only the tumor, and not healthy parts of your body.
On the day of treatment, you’re carefully put into the right position. You may see lights from the machine lined up with the marks on your skin. These help the therapist know you’re in the right position. The therapist will leave the room while the machine sends radiation to your tumor. During this time, he or she can see you, hear you, and talk to you. When the machine sends radiation to your tumor, you’ll need to be very still. But you don’t have to hold your breath. The process will likely take less than an hour.
What are common side effects of radiation therapy for anal cancer?
Radiation affects both normal cells and cancer cells. This means it can cause side effects. Some side effects can be treated. They may even get better or go away over time after treatment ends. Here are some common side effects of radiation for anal cancer:
Skin irritation, redness, blistering, itching, or burning in the treated area
Diarrhea, sometimes with some rectal bleeding
Discomfort when having a bowel movement
Nausea and vomiting
An urgent need to urinate
Tiredness or fatigue
Working with your healthcare provider
It's important to know what kind of radiation treatment you are getting. Ask your healthcare team how the radiation will work and what side effects you might have. Ask about what can be done to help prevent or ease them.
Talk with your healthcare team about what signs to look for and when to call them. For instance, radiation for anal cancer can cause diarrhea, bleeding, and other bowel problems. Make sure you know what number to call with questions. Is there a different number for evenings and weekends?
It may be helpful to keep a diary of your side effects. Write down physical, thinking, and emotional changes. A written list will make it easier for you to remember your questions when you go to your appointments. It will also make it easier for you to work with your health care team to make a plan to manage your side effects.