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Radiation Therapy to the Pelvis for Cancers of the Colon, Rectum and Anus

This information will help prepare you for radiation therapy to the pelvis. Before you begin your treatment, you will have a treatment planning procedure called a simulation. This is done to make sure that

  • Your treatment site is mapped out
  • You get the right dose of radiation
  • The dose to nearby tissue is small

During your simulation, you will have x-rays and your skin will be marked. These marks identify the area that will be treated. Your simulation will take 2 to 4 hours.

Preparing for Your Simulation

If you think you will be uncomfortable while lying still for a long time, bring acetaminophen (Tylenol®) or your usual pain medicine to your simulation. Take it when you arrive for the procedure. If you think you may get anxious during your procedure, speak with your radiation oncologist about medication that can be helpful.

Some patients need to have a Positron Emission Tomography-Computed Tomography (PET-CT) scan done during the simulation. If you are having one, a nurse will give you detailed instructions to prepare you for your PET-CT scan.

If you are having a PET-CT, don't eat or drink anything except plain water 6 hours before your appointment time. This includes gum, hard candy, cough drops, and mints. If you have had anything except water, your PET-CT scan may need to be rescheduled.

Day of Your Simulation

When you arrive for your simulation, a radiation therapist will greet you. He or she will take a photograph of your face. This picture will be used to identify you throughout your treatment. The therapist will then explain the procedure to you.

If you have not already signed a consent form, your radiation oncologist will review everything with you. You will then be asked to sign the consent form.

You will drink 2 glasses of water 1 hour before your simulation and on each day of your treatment. This will make your bladder full and will push away your small intestine from the field of radiation. You will also be asked to drink about 1 cup of liquid contrast. This helps us see your small intestine on the simulation x-rays that will be taken later.

During Your Simulation

For your simulation, you will get undressed from the waist down and change into a gown. You may keep your shoes on. The therapists will help you lie on a table on your stomach. You will lie in the same position each time you receive your radiation treatment. Although the simulation table will have a sheet on it, the table is hard and has no cushion. If you haven't taken pain medication and think you may need it, tell the therapists before your simulation begins.

Throughout your simulation, you will feel the table move to different positions. The lights in the room will be turned on and off and you will see red laser lights on each wall. The therapists use these laser lights as a guide when they position you on the table. Don't look directly into the red beam because this may hurt your eyes.

Although the therapists will walk in and out of the room during your simulation, there will always be someone who can see and hear you. During your simulation, you will hear the therapists speaking to each other as they work. They will explain what they are doing, but please don't speak once they begin because it may change your position. You can speak if you are uncomfortable or need assistance.

To help pass the time, music can be played throughout your procedure. If you would like, ask the radiation therapist to play a CD for you. You may bring one of your own from home.

X-ray images

X-ray images will be taken of the area to be treated while you are lying on your stomach. These may be done on an x-ray machine called a simulator, on a computed tomography scan machine called an AcQ-Sim, or on a PET-CT scan machine. It takes about 45 minutes to get the x-ray images.

Skin markings (tattoos)

The therapists will draw on your skin with a felt marker. Then, they will make permanent skin markings, called tattoos, with a sterile needle and a drop of ink. The sensation of getting a tattoo feels like a pinprick. The tattoo marks are no bigger than the head of a pin. You will receive 5 to 7 tattoos across your lower back. The felt markings can be washed off after your simulation. The tattoos are permanent and will not wash off.

After the tattoos are made, the therapists will take several photographs of you in your simulation position. The photographs and tattoo marks will be used to position you correctly on the table each day of your treatment.

After Your Simulation

If you were given liquid contrast to drink during your simulation, drink a lot of water when you get home. It will help you pass the contrast.

At some point during your simulation, a therapist will ask you what time of day you would like to have your radiation treatments. We will try to give you the time you like. However, we need a 2-hour window because the time you prefer may not be open. We will move you to that time slot once it becomes open. Please know that we will do our best to give you the appointment time you want as soon as we can.

At the end of your simulation, we will make an appointment for your set-up procedure. This is the final appointment before your treatment begins. During the time between your simulation and your set-up procedure, your radiation oncologist will work with a team to plan your treatment. This takes between 5 days and 2 weeks.

Set-up Procedure

Before your first treatment, you will be scheduled for a set-up procedure. This procedure usually takes about 1 hour. If pain medication was helpful during your simulation, you may want to take it before this procedure.

When you come for your procedure, you will change into a gown. The therapists will bring you to the room where you will receive your treatment each day. They will position you on the table. You will lie exactly as you did the day of your simulation. Beam films (x-rays of each of the radiation beams) will be taken to make sure that your position and the area being treated are correct. They are not used to see how your tumor responds to treatment. You will start your treatment within several days after your set-up procedure.

During Your Radiation Treatment

Treatment schedule

Radiation treatment is given daily, Monday through Friday, for about _____ weeks. Plan an extra week to allow for unexpected events (e.g., bad weather). You will be in the department for about 60 minutes each day. You must come in every day for your treatment. Treatment may not be as effective if you skip or miss appointments. However, you may have 1 or 2 scheduled days off for the machines to be maintained. If you need to change your schedule for any reason, please speak with your therapists.

Some patients get chemotherapy and radiation treatment on the same day. It can be given before or after your radiation therapy. The timing doesn't matter.

Treatment

After you check in at the reception desk, have a seat in the waiting room. When they are almost ready for you, the therapists will tell you to change into a gown. When they bring you into the treatment room, the therapists will help you lie on the table. Once you are positioned correctly, the therapists will leave the room, close the door, and begin your treatment.

While lying on the table, men should position their penis down, towards their feet. If uncircumcised, pull back the foreskin to expose the head of the penis. This will help prevent a skin reaction to the tip of the penis. You will not see or feel the radiation, but you may hear the machine as it moves around you and is turned on and off. You will be in the treatment room for 10 to 30 minutes, depending on your treatment plan. Most of this time will be spent putting you into the correct position. The actual treatment only takes a few minutes.

Although you are alone during your treatment, the therapists can see you on a monitor and hear you through an intercom at all times. Breathe normally during the treatment, but don't move. If you are very uncomfortable and need help, speak to the therapists. They can turn off the machine and come in to see you at any time, if necessary.

Weekly visits during your treatment

Your radiation oncologist and nurse will see you each week to evaluate your response to treatment. This visit will be before or after your treatments each _______________. You should plan on being in the department about 1 extra hour on those days. During these visits, you should ask questions and discuss any concerns you have. If you need to speak with your radiation oncologist or nurse any time in between these weekly visits, ask the support staff or therapists to contact them when you come in for treatment.

Side Effects

Some patients develop side effects from radiation treatment. The type and how severe they are depend on many factors. These include the dose of radiation, the number of treatments, and your overall health. Side effects may be worse if you are also getting chemotherapy. Below are the most common side effects of radiation treatment to the pelvis. You may have all, some, or none of these.

Gastrointestinal (stomach and bowel) problems

Common symptoms within weeks after treatment begins are

  • Diarrhea
  • Abdominal cramping
  • Constipation
  • Pressure and discomfort in the rectum

Below are guidelines to help you manage these problems. Continue to follow them until your bowel movements return to your usual pattern. This may take 2 to 4 weeks after your treatment is completed.

  • Take a sitz or tub bath to help relieve discomfort in the rectum. Use warm water and stay in the water no longer than 15 minutes at a time. You may take baths as often as you like for comfort.
  • If you have diarrhea, take Imodium®. Please follow the directions below and not what is printed on the package.
    • Take 4 mg by mouth followed by 2 mg after each loose stool (feces). You may take up to 16 mg in a 24-hour period.
    • Drink at least 8 glasses of clear liquids per day. This will replace the liquids you lose from diarrhea.
    • Use with caution if you have a history of liver or kidney disease.
    • Call your radiation oncologist or nurse if you develop
      • A temperature of 100.4° F (38° C) or higher
      • Black or bloody stool
      • Dizziness
      • Symptoms that last more than 2 days
  • Take pain medication if you have cramping or discomfort in your rectum. Your radiation oncologist will tell you what to take and how to take it.

Dietary guidelines

We recommend a low-fat and low-fiber diet when you have diarrhea, gas, and bloating during treatment. This means you must eat less than 12 grams per day of fiber and less than 40 grams per day of fat. It is important to watch how you react to the foods you eat. Certain foods or beverages can make your symptoms worse.

You should follow this diet until your bowel movements return to normal. Then, you can slowly start adding 1 food from your usual diet at a time. A dietitian is available to answer any questions and concerns about your diet.

Food Category Recommended Foods Foods to Avoid
Fats
  • Low-fat or non-fat varieties of margarine, mayonnaise, salad dressings, and sauces
  • Small amount of butter and oil (e.g., pat of butter with toast)
  • Avocado
  • Full-fat sauces and creamy salad dressings
  • Excess amounts of butter and oil
Fruits
  • Canned fruits
  • Applesauce or other fruit purees
  • Ripe bananas
  • Peeled and cooked fresh fruits (e.g., baked apples)
  • Marmalade and jams without seeds or skin
  • Uncooked fresh fruits (except bananas)
  • Dried fruits
  • Fresh fruit smoothies
  • Marmalade or jams with seeds or skin
Meats and Meat Substitutes
  • Lean meats that are well-cooked and trimmed of any visible fat
  • Skinless poultry (chicken and turkey)
  • Fish
  • Eggs
  • Meats or fish packed in water
  • Low-fat tofu
  • Hummus (chickpea) spread
  • High-fat meats (e.g., spare ribs and sausage)
  • Veggie burgers made with whole grains or beans
  • Any item packed in oil
  • High-fat tofu
  • Legumes (beans, peas, and lentils)
Vegetables
  • Well-cooked or canned vegetables without seeds or skin (carrots, beets, asparagus tips, white potatoes without skin, green beans, and marinara sauce)
  • Raw vegetables and any cooked or canned vegetables with seeds or skin
  • Vegetables that can cause gas (broccoli, cauliflower, cabbage, Brussels sprouts, onions, and beans)
Soups
  • Any low-fat, broth-based soups made with allowed vegetables
  • Avoid all others
Beverages
  • Any non-carbonated and non-caffeinated clear liquid beverages
  • Juices without pulp
  • Herbal teas
  • Lactose-free, low-fat, or non-fat milk
  • Carbonated beverages
  • Coffee (both decaf and regular)
  • Caffeinated teas
  • Fresh fruit juices with pulp
  • Prune juice
  • Regular milk
  • Alcohol
Dairy Products
  • Lactose-free, non-fat or low-fat milk or cheeses
  • Non-fat or low-fat plain or flavored yogurts without seeds or skin
  • Lactose-containing full-fat milk or cheeses
  • Fruit-flavored yogurts with seeds or skin
Breads
  • Low-fiber, whole-wheat bread (less than 2 grams of dietary fiber per serving)
  • White or seedless rye bread
  • Plain crackers, graham crackers, or animal crackers
  • Waffles and pancakes
  • Low-fat muffins without dried fruit or nuts
  • High-fiber, whole-wheat bread or whole-grain bread
  • Wheat crackers
  • Full-fat baked goods (e.g., muffins, biscuits, and doughnuts)
  • Any items made with whole grains
Cereals and Grains
  • Refined cereals (e.g., puffed wheat or rice, corn flakes, Cheerios®, oatmeal, and cream of wheat)
  • White rice or pasta
  • Plain couscous and orzo
  • Rice cakes
  • Multigrain or bran cereals
  • Cereals with nuts, seeds, or dried fruit, including granola
  • Whole grains (e.g., brown rice, wild rice, quinoa, and barley)
  • Whole-wheat or whole-grain pastas
Desserts
  • Low-fat plain cakes and cookies without dried fruit or nuts
  • Fruit ice, popsicles, or sherbet
  • Gelatin (i.e., Jell-O®)
  • Any desserts with nuts, seeds, coconut, or dried fruits
  • Rich dessert of any kind (e.g., pies, custards, and cakes)
Miscellaneous
  • At least eight, 8-ounce glasses of clear liquids per day
  • Fluids with electrolytes (e.g., Gatorade®, Pedialyte®, chicken broth, and coconut water)
  • Lactose-free, liquid nutritional supplements (e.g., Ensure®, Boost®)
  • Hot and spicy foods
  • Fried foods or fast foods
  • Frequent intake of sugar-free products with sorbitol (a sugar alcohol), unless you have high blood sugar

Loss of appetite

Some patients find that their appetite decreases during treatment. It is important that you maintain your weight during your treatment. Your body needs enough protein and calories to help you recover from your treatment. Below are suggestions to help you maintain your weight.

  • Choose foods that increase your intake of calories and protein. Protein-rich foods you can eat include
    • Lean meats
    • Eggs
    • Skinless poultry
    • Low-fat yogurt
    • Fish
    • Lactose-free dairy items
    • Low-fat tofu
  • Try to eat small meals often throughout the day. If you never seem to feel hungry, make a schedule to make sure you eat regularly (for example, every 2 hours).
  • Eat your meals slowly in a relaxing setting. Eat with family or friends whenever possible.
  • Vary the color and texture of your foods to make them more appealing.
  • Bring snacks and drinks with you when you come in for treatment. You can have these while you are waiting or while you are coming to and from the department each day.
  • Drink liquid nutritional supplements if you are not eating enough food. There are many products available, and they come in many flavors. Ask your dietitian which product is best for you.
  • You may take a daily multivitamin if you wish. Don't take more than the recommended daily amount of any vitamin. If you are drinking at least 4 servings per day of an oral nutritional supplement, such as Ensure®, stop taking your multivitamin. These supplements give you as many vitamins and minerals as a multivitamin. Don't take any supplements unless your radiation oncologist approves them. This includes both nutritional and herbal supplements.
  • Ask your radiation oncologist or nurse for the booklet, Eating Well During and After Your Cancer Treatment, which includes helpful sample menus.

Urinary changes

The lining of your bladder may become irritated during your treatment. About 2 weeks after starting treatment you may have

  • Frequency of urination
  • Urgency to urinate
  • Burning with urination
  • Difficulty passing urine

Below are guidelines to help you manage these problems.

  • Drink 2 to 3 quarts of liquids throughout the day.
  • Avoid caffeine, alcohol, pepper, and spicy foods. These may irritate your bladder.
  • Let your radiation oncologist or nurse know if you have any urinary changes. Your radiation oncologist can prescribe medication to relieve these symptoms.

Skin reactions

During radiation therapy, your skin and hair in the area being treated will change. This is normal and expected. After 2 or 3 weeks, your skin will become pink or tanned. As treatment goes on, it may become bright red or very dark. It may also feel dry and itchy, and it may look flaky.

Some people develop a rash in the area being treated. Although this may be a side effect of treatment, a rash could be a sign of infection. If you develop a rash at any time during your treatment, tell your radiation oncologist or nurse so that you can be evaluated.

You may also lose some or all of your pubic hair. The hair will usually grow back 2 to 4 months after treatment is completed.

Below are guidelines to help you care for your skin during treatment. Follow these guidelines until your skin gets better. These guidelines refer only to the skin in the area being treated.

Keep your skin clean

  • Bathe or shower daily using warm water and a mild unscented soap, such as Dove®, Basis®, or Cetaphil®. Rinse your skin well and pat it dry with a soft towel.
  • When washing, be gentle with your skin in the area being treated. Don't use a washcloth or a scrubbing cloth or brush.
  • The tattoo marks are permanent and won't wash off. You may get other markings during treatment, such as an outline of your treatment area with a purple felt-tipped marker. Use mineral oil to remove these lines when the therapists tell you they can be washed off. Don't use alcohol or alcohol pads on the skin in the area being treated.

Moisturize your skin often

  • Start using a moisturizer when you begin treatment. There are a few over-the-counter moisturizers you can use, such as Aquaphor® or Eucerin®. There are a number of other products that are also good to use, and your nurse may recommend 1 of these to you. Use only 1 at a time, unless your nurse tells you to use more. Please note that using aloe vera directly from the plant is more likely to cause an allergic reaction than using a pure aloe vera gel. We recommend that you use the pure aloe vera gel.
  • Apply the moisturizer 2 times a day. Your nurse will tell you if you need to do it more or less often.
  • Don't wash off the moisturizer before your treatments. This could irritate your skin.
  • If you are treated in the morning, apply the moisturizer
    • After your treatment
    • Before you go to bed
  • If you are treated in the afternoon, apply the moisturizer
    • In the morning, at least 4 hours before your treatment
    • Before you go to bed
  • On the weekends, apply the moisturizer
    • In the morning
    • Before you go to bed

Avoid irritating the skin in the area being treated

  • Wear loose-fitting cotton clothing in the area being treated. Avoid tight clothing that will rub up against your skin.
  • Use only the moisturizers, creams, or lotions your radiation oncologist or nurse recommend.
  • Don't use makeup, perfumes, or powders in the area being treated.
  • If your skin is itchy, don't scratch it. Tell your nurse so he or she can recommend how to relieve the itching.
  • Don't shave over your treated skin.
  • Don't use any tape on your treated skin.
  • Don't let your treated skin come into contact with extreme heat or cold temperatures. This includes hot tubs, water bottles, heating pads, and ice packs.
  • If you don't have skin problems during your treatment, you may swim in a chlorinated pool. However, be sure to rinse off the chlorine immediately after leaving the pool.
  • Avoid tanning or burning your skin during and after your treatment. If you are going to be in the sun, use a PABA-free sunblock with an SPF of 30 or higher. Also, wear clothing that covers you as much as possible.

Fatigue

Most patients develop fatigue (i.e., sleepiness, weakness, and not being able to concentrate) after 2 or 3 weeks of treatment. This may last for several months. There are a lot of reasons patients develop fatigue during treatment, including

  • The effects of radiation on your body
  • Traveling to and from treatment
  • Not having enough restful sleep at night
  • Not eating enough protein and calories
  • Having pain or other symptoms
  • Feeling anxious or depressed

Some patients find that their fatigue is worse at certain times of the day. Below are suggestions to help you manage your fatigue.

  • If you are working and are feeling well, continue to do so. However, working less may help increase your energy.
  • Plan on doing your daily activities when you have the most energy.
  • Plan time to rest or take short naps during the day, especially when you feel more tired. You may also find it helpful to go to sleep earlier at night and get up later in the morning.
  • Ask family and friends to help you with shopping, cooking, and cleaning.
  • Some patients have more energy when they exercise. If your radiation oncologist approves, try light exercise such as walking.
  • Eat foods that are high in protein and calories.
  • Ask your radiation oncologist or nurse for help with other symptoms you may have. Medication can be given for pain, nausea, depression, anxiety, and sleep problems.

Changes to your blood cell counts

Bone marrow is the substance inside bone that makes blood cells. You have 3 kinds of blood cells. White blood cells fight off infection. Platelets help your blood to clot. Red blood cells carry oxygen needed for energy.

You may have lowered blood cell counts when large areas of bone marrow are in the area being treated. If you are also getting chemotherapy, it can also impact your blood cell count.

We will monitor you throughout your treatment with a blood test called a complete blood count (CBC). If your counts drop, we may stop your treatment until they return to higher levels. We will discuss precautions with you.

Call Your Doctor or Nurse Immediately if You Develop

  • A temperature of 100.4° F (38° C) or higher
  • Shaking chills
  • Flu-like symptoms
  • Bleeding

You may need to be seen to have your blood counts checked and to make sure you don't have an infection.

Sexual Health

  • You may be sexually active during your treatment unless your radiation oncologist tells you otherwise. However, if you are of childbearing age, you must use contraception so you will not get pregnant during your treatment.
  • You may have concerns about the effects of cancer on your sexuality. An excellent resource is the booklet Sexuality and Cancer. There are 2 versions available, one for men and one for women. You can get a copy from the American Cancer Society. Call 1-800-227-2345 and tell them which version you want.
  • MSKCC has a Sexual Health Program to help patients address the impact of their disease and treatment on sexual health. You can meet with a specialist before, during, or after your treatment.
    • Female Sexual Health Program: call (646) 888-5076 for an appointment
    • Male Sexual Health Program: call (646) 497-9068 for an appointment

For Women Only

Changes to the vagina

Your vagina may become irritated during treatment. About 2 weeks after starting treatment, you may have some vaginal discharge and discomfort. This may last 2 to 4 weeks after your treatment is completed. Some patients also have vaginal dryness and tightening after treatment is completed. These changes are permanent. How severe these changes are depends on

  • The area that was treated
  • The dose of radiation
  • The type of radiation
  • Whether or not you are receiving hormone replacement therapy

Your radiation oncologist and nurse will give you information about how you are likely to be affected. About 1 month after your treatment ends, your nurse will tell you how to manage vaginal dryness and tightening. You will learn about lubricants, moisturizers, and vaginal dilators. Below are ways you can increase your comfort.

  • Take sitz or tub baths to relieve vaginal discomfort. Use warm water and stay in the water no longer than 15 minutes at a time. You may take these baths as often as you like for comfort.
  • Use pantiliners for discharge; don't use tampons.
  • Use the moisturizer your nurse gives you for itching and irritation of the labia.
  • Check with your radiation oncologist or nurse before douching. It may increase irritation.
  • If your vagina is irritated, use a vaginal lubricant during sexual intercourse, such as Astroglide® or KY® Jelly. Using condoms during intercourse will help prevent a vaginal infection.
  • If you are having discomfort during intercourse, wait for 1 or 2 weeks to heal. Then, try to do it again.

Hormonal changes

Your ovaries will be affected if they are in the area being treated. If you are premenopausal (have not yet gone into menopause), your periods will stop.

Menopause will begin after your treatment is completed. If you have menopausal symptoms, tell your radiation oncologist or nurse. Common symptoms are hot flashes, insomnia, and mood swings. Ask your radiation oncologist about treatment options for these symptoms.

Fertility

You must use birth control during your treatment if you are fertile (able to have a baby). Don't conceive a child until 2 years after your treatment is completed. If you plan to conceive a child after your treatment, please discuss this thoroughly with your radiation oncologist before you begin your treatment.

Emotional Health

The diagnosis and treatment of cancer can be a very stressful and overwhelming event. You may feel depressed, anxious, confused, afraid, or angry. You may have strong feelings about any permanent changes. These changes can have an impact on your emotional and mental well-being. Help is available for you at any time. If you would like counseling, your nurse can give you a referral to see a social worker, psychiatrist, or counselor.

Also, you may find it comforting to speak with a cancer survivor or caregiver who has been through a similar treatment. Through our Patient-to-Patient Support Program, you have the chance to speak with former patients and caregivers. To learn more about this service, please call (212) 639-5007.

After Your Radiation Treatment

Please be sure to keep your follow-up appointments with your radiation oncologist. He or she will evaluate your response to treatment. You may have blood tests, x-rays, and scans during these visits. Before coming, write down your questions and concerns. Bring this and a list of all your medications. If you are running low on any medication you need, let your radiation oncologist know before you run out.

The MSKCC Resources for Life After Cancer Program provides support services after your treatment is finished. To learn more about these services, call (646) 888-4740.