Image-Guided Radiation Therapy

This information will help prepare you for image-guided radiation therapy (IGRT), including what to expect before, during, and after your treatment. You will also learn about side effects and how to care for yourself during your treatment.

Radiation therapy is the use of high-energy x-rays to treat cancer. A beam of radiation is directed to the tumor site from a treatment machine. The beam passes through the body and destroys cancer cells in its path. IGRT is a procedure that can treat tumors with even more accuracy. It involves taking many images of the tumor during treatment. This ensures that we are aiming the beam of radiation to the correct area.

IGRT is used in a number of situations. Examples are when:

  • Radiation therapy is given in 1 to 5 treatments instead of multiple treatments.
  • For safety reasons, the treatment needs to be very precise.
  • We treat a part of the body in which there is movement. It may be:
    • A tumor in the lung or liver that moves with breathing
    • A tumor in the abdomen or pelvis that may move due to fullness or movement of the digestive tract
    • A tumor in the spine or surrounding areas


Before you begin 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 taken 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 medication to your simulation. Take it 1 hour before your procedure. If you think you may get anxious during your procedure, speak with your doctor about medication that can be helpful.

For some patients, special procedures must be done before the simulation to help in planning. We will schedule these for you.

  • Placement of markers: Several gold seeds will be implanted into the area to be treated. These markers can be seen on x-rays and a computed tomography (CT) scan. This will be done a number of days before your simulation. You will be told where to go to have it done. Someone from the Pre-Surgical Center will contact you the day before to give you instructions and to confirm the time of your arrival.
  • Myelogram: A contrast dye will be injected into your spinal canal. It helps us see your spinal cord and surrounding tissues more clearly. This is done several hours before your simulation. Someone from Radiology will contact you the day before to confirm the time of your arrival and tell you where to check in. If you do not receive a call by 4:00 pm, please call 212-639-7298.

Day of your simulation

Unless your doctor or nurse has told you otherwise, you may follow your usual diet on the day of your simulation. Wear comfortable clothes, and be sure not to wear earrings or necklaces to your appointment.

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 are having a myelogram, this will be done first. Then, you will be brought back to the department on a stretcher after you have recovered.

During your simulation

For the simulation procedure, you may need to get undressed and change into a gown. The therapists will have you empty your bladder and then help you lie down on a simulation table. Although the table will have a sheet on it, it 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. Also, the room is usually cool. If you feel uncomfortable at any time, let the therapists know.

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. Do not 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. You will hear the therapists speaking to each other as they work. They will explain what they are doing, but please do not 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 during your procedure. If you would like, ask the therapists to play a CD for you. You may bring one of your own from home.

Positioning and molds

Depending on the area being treated, frames, molds, or masks may be made. These will help you stay in the correct position and will be used with each treatment. It takes about 30 minutes to make these.

  • Body mold: A plastic-like bag filled with warm liquid will be placed under you while you are lying on your back. It will shape around your body and harden as it cools.
  • Paraspinal frame: You will lie on your back within a frame, with your hands holding the handles at your sides. The frame lines up your shoulders and hips to keep you in proper alignment.

  • Abdominal compression: You will lie on your back. You will be asked to put on a harness-like jacket with an air bladder. The air bladder will lie across your lower abdomen. Air will be instilled into the air bladder, creating pressure. This is to minimize the movement of your liver while we are taking x-ray images.

  • Face mask: The therapist will place a warm, wet sheet of plastic mesh over your face and will shape it to fit around your head. You will be able to hear and breathe without difficulty while the mask is on. As the mask cools, it will harden.

  • You will probably be lying on your back throughout your simulation. A mold may be made of your upper body to help you maintain the same position each time you receive your treatment. The therapists will pour a warm fluid into a large plastic bag that will be sealed and placed on the table. You will lie on top of the bag, on your back, with your arms raised above your head. The fluid will feel warm at first, but it will cool as it hardens. While it is cooling, the therapist will tape the bag to your skin so that it will take the shape of your upper body and arms. This procedure takes about 15 minutes. During your simulation, and each day of your treatment, you will lie in this mold to help ensure you are in the correct position.

X-ray images

While you are lying in position, x-ray images will be taken of the area to be treated. These will be done on a specialized CT scan. These CT scans are used only to map your treatment plan. They are not used for diagnosis or to find tumors. During the scan, you will hear the machines as they are turned on and off. Even if the noise seems loud, the therapists will be able to hear you if you need to speak with them. It will take about 45 minutes to have your x-rays taken.

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 in the area being treated. 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.

Additional imaging

For some patients, we need to use other imaging tests with the CT scan to help us plan your treatment. These are done the same day as your simulation, right after the procedure. We will schedule these for you and bring you to the area where they will be done. If you think you will feel anxious during these procedures, ask your doctor about medication that may help you relax.

  • Magnetic resonance imaging (MRI): This procedure will be done in the Department of Radiation Oncology while you are in the body mold we made during your simulation. It helps us see your spine
    more clearly.
  • Positron emission tomography (PET) scan: This procedure will be done while you are in the body mold we made during your simulation. It helps us see the difference between normal and abnormal tissues. This will be done in either the Department of Radiation Oncology or the Nuclear Medicine Department.
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Planning Your Treatment

During the time between your simulation and first treatment, your radiation oncologist will work with a team to plan your treatment. They will use your simulation x-rays, CT scan, and any other imaging tests that were done to plan the angles and shapes of your radiation beams. They will also determine the dose of radiation that your body will receive. These details are carefully planned and checked. This process takes about 7 business days.

Treatment schedule

At the end of your simulation, you may be given an appointment card with the date and time for your first treatment. If your appointment cannot be made then, we will call you to tell you the date and time.

IGRT may be given in several different schedules. Your schedule is based on what your doctor recommends.
It can be:

  • A single treatment, usually given on the same day as your setup or beam films
  • Three treatments, usually given every other day
  • Daily treatment, given Monday through Friday, for about _____ weeks

Your 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.

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During Your Treatment

After you check in at the reception desk, have a seat in the waiting room. If you are taking any pain medication, you should take it at this time. When they are almost ready for you, the therapists will tell you to change into a gown and go to the bathroom. When they bring you into the treatment room, the therapists will help you lie in your mold on the table. Once you are positioned correctly, the therapists will leave the room, close the door, and start your treatment.

On the day of your first treatment, the therapists will take special x-rays called beam films. These x-rays are done to make sure your position and the area being treated are correct.

After the beam films are taken, you will have your treatment. 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 about
2 hours, depending on your treatment plan. Most of this time will be spent putting you into the correct position.

If you are getting more than 1 treatment, the next one may last 30 minutes to 2 hours, depending on your treatment plan. You can ask for music to be played while you are in the treatment room. You can bring a CD from home if you would like.

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 your treatment, but do not 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 anytime in between these weekly visits, ask the support staff or therapists to contact them when you come in for treatment.

If you are receiving 1 or 3 treatments, your radiation oncologist and nurse will see you at least once during your treatment.

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Side Effects

Some patients develop side effects from radiation therapy. 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 therapy. You may have all, some, or none of these. Depending on the area being treated, there may be other side effects that your doctor and nurse will discuss with you.

Many patients ask about vitamins. You may take a daily multivitamin if you wish. Do not take more than the recommended daily amount of any vitamin. Do not take any supplements unless your radiation oncologist approves them. This includes both nutritional and herbal supplements.

Swelling around the treatment area

Radiation therapy may cause swelling around the treatment area. You may need to take a steroid called dexamethasone (Decadron®) to prevent it. Whether you need it depends on the area we are treating and the amount of radiation you will be getting. If you need the steroid, you will be told how to take it before and after your treatment. Be sure to take it exactly as you are told.

If you develop any symptoms after your treatment, such as increased pain or difficulty moving, call your doctor or nurse immediately. The dose may need to be adjusted or you may need additional medication.

Skin and hair 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 look flaky.

Sometimes, the skin in sensitive areas may blister, open, and peel. If this happens, tell your doctor or nurse. Your nurse can apply special bandages or creams and teach you how to care for your skin. The skin reactions sometimes become worse during the week after your treatment is completed. If this happens, call your doctor or nurse. Your skin will gradually heal 3 or 4 weeks after your treatment is completed.

You may also lose some or all of the hair on the area being treated. Depending on the dose given, the hair will usually grow back 2 to 4 months after your 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. Do not use a washcloth or a scrubbing cloth or brush.
  • The tattoo marks you received before treatment 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.
  • Do not 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. This can help to minimize any skin reactions. There are a few over-the-counter moisturizers you can use, such as Aquaphor®, Eucerin®, and pure aloe vera gel. 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. 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.
  • Apply the moisturizer 2 times a day. Your nurse will tell you if you need to do it more or less often.
  • Do not wash off the moisturizer before your treatments. Your skin could become irritated.
  • 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 your skin in the area being treated

  • Wear loose-fitting cotton clothing and undergarments in the area being treated. Avoid tight clothing that will rub up against your skin.
  • Use only the moisturizers, creams, or lotions your doctor or nurse recommend.
  • Do not use powders in the area being treated.
  • Do not put any tape on your treated skin.
  • If your skin is itchy, do not scratch it. Tell your nurse so he or she can recommend how to relieve the itching.
  • Do not shave over your treated skin. If you must shave, use only an electric razor. Discontinue this if your skin becomes irritated.
  • Do not expose your treated skin to extreme hot or cold temperatures. This includes hot tubs, water bottles, heating pads, and ice packs.
  • If you do not have skin problems during your treatment, you may swim in a chlorinated pool. However, be sure to rinse off the chlorine immediately after getting out of 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.


Most patients develop fatigue (i.e., lack of energy, sleepiness, weakness, and not being able to concentrate) after 2 or 3 weeks of treatment. This will gradually go away after your treatment is done, but can 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 your daily activities. Pick those things that are necessary and most important to you and do them 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 doctor approves, try light exercise such
    as walking.
  • Eat foods that are high in protein and calories.
  • Some patients have symptoms such as pain, nausea, diarrhea, difficulty sleeping, or feeling depressed
    or anxious. These can all increase your fatigue. Ask your doctor or nurse for help with any other symptoms you may have.

Other side effects you may experience:

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, 1 for men and 1 for women. You can get a copy from the American Cancer Society. Call 1-800-227-2345 and tell them which version you want.

MSK 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 Medicine and Women’s Health Program: call 646-888-5076 for an appointment
  • Male Sexual and Reproductive Medicine Program: call 646-888-6024 for an appointment

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.

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After Your Treatment

Please be sure to keep your follow-up appointments with your oncologists. They 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 doctor know before you run out.

The MSK Resources for Life After Cancer (RLAC) Program provides support services after your treatment is finished. To learn more about these services, call 646-888-8106.

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If you have any questions or concerns, talk with a member of your healthcare team. You can reach them Monday through Friday from 9:00 am to 5:00 pm at ____________________. After 5:00 pm, during the weekend, and on holidays, please call____________________. If there’s no number listed, or you’re not sure, call 212-639-2000.
Image-Guided Radiation Therapy
©2016 Memorial Sloan Kettering Cancer Center - Generated on February 9, 2016