Fractionated Stereotactic Radiotherapy -A Patient Guide
Fractionated Stereotactic Radiotherapy is a precise way to aim beams of radiation, from many angles, to cover a tumor. The treatment is split into a number of smaller doses (fractions) of radiation. By doing this, the effects on the normal, healthy tissues are reduced while the tumor receives the desired treatment.
Types of tumors are treated with Fractionated Stereotactic Radiotherapy
- brain tumors, both benign and malignant
- metastatic brain lesions
- non-tumor lesions in the brain such as Arterio-Venous Malformations (AVM)
- vestibular schwannomas or acoustic neuromas
- meningiomas
- certain types of head and neck cancers, such as cancer of the tonsil, larynx, tongue, sinus, base of skull, and mouth
Before your treatment
Before treatment can begin, you will need a bite tray, head mold and face mask. The bite tray is used to help us place you in the same position for every treatment. The head mold and face mask are used to keep your head from moving. We will need to look at your teeth before the bite tray is made to make sure that you do not have loose teeth, fillings or caps. A loose tooth, filling or cap could be pulled out when taking the bite tray out of your mouth. If you know that you have loose teeth, please see your dentist before being fitted for a bite tray.
Step A: bite tray, head mold, facemask and CT scan. These steps will take about 2-3 hours to complete.
The Bite Tray
The bite tray takes about 20 minutes to make. You will sit upright. You will be given a white plastic mold and asked to insert it into your mouth a few times. This helps you practice taking the tray in and out of your mouth and checks for proper fit and size. Once the right size has been chosen, you will insert the tray again. This time it will contain a molding material. You will bite down on the tray with moderate force, about as hard as you would bite into a piece of fruit. You need to hold the bite for 4-5 minutes. Do not chew or try to talk while the mold is being made.
After the tray has hardened you will remove it. It will be hard to remove. The bite tray will be checked to be sure that we have a proper mold. You will insert and remove it until you become comfortable with the fit. We check the fit. As the bite tray hardens, we will make the facemask and head mold.
The Head Mold
The head mold takes about 5-10 minutes to make. You lie on a table in a comfortable position. We place a foam-filled cloth under your head. The mold will be cool and wet when it is placed under your head and slowly warms and dries as it hardens. The foam mold has a strong odor that will go away as the mold hardens. As you are lying on the table we sculpt the mold around your head. Please keep your head still during this time. Please do not wear turtlenecks or high-necked sweaters on this day. They will get in the way of the molding process. If you have long hair, please wear it down or in a low ponytail. If you wear any hair clips or barrettes, they must be removed before the head mold and face mask are made.
The Face Mask
The face mask takes about 15-20 minutes to make. You lie back on the table with the head mold in place. A mesh film is placed across the top of your head, forehead, and nose, ending at your top lip. The mesh is flexible plastic that is placed in warm water. As it molds to your face, it becomes stiff. The face mask will be molded to fit the contours of your eyes and your nose. It is important that the mask fit snugly around these features. The mask takes about 10-15 minutes to harden around your face. As it hardens you will feel the mask tighten slightly. It will not hurt, but you will notice it. We need to lightly press on your eyes and mold the mask to the bridge of your nose. After the mask is made, you will be able to open your eyes slightly, but not all the way because of the way the mask is molded. You may wish to breathe through your mouth while the mold is being made because the mask will conform to your nose. If you are claustrophobic or afraid of being in confined spaces, please let us know.
The CAT (CT) Scan
After the bite tray, head mold, and facemask are made, a CT scan will be done. If you have never had a CT scan before please let your nurse know so you can be given a handout that explains it. The scan is the final step before we can begin planning your treatment. If IV contrast is needed a blood test called a creatinine level will be done to make sure that your kidneys are working well. Your local doctor can do the test or it can be done here. An IV will be placed. It will be used to give the contrast. This will give us a better picture of your tumor. Some people feel a warm flush or have a metal or strange taste in their mouth with the contrast. This is normal and will go away after it is finished.
If you have an allergy to the CT contrast or are allergic to shellfish or iodine products please let your doctor or nurse know.
If you have diabetes and take oral medicines (specifically, Glucovance®, metformin, Metaglip®, Avandamet® or Glucophage®) or insulin to control your diabetes, please let your nurse or doctor know. You should NOT take this the day of your scan and for 48 hours after the injection of contrast. We may need to find a short-term plan to manage your blood sugars until you can resume this medication. This may involve talking to your primary doctor.
Once the contrast is about halfway infused, you will be asked to insert the bite tray. Since you will have your eyes closed, this may be hard to do at first. We will place a strap under your chin to help you hold the bite tray in place.
After all three pieces are in place, and the contrast (if needed) has been given, the CT scan will be done. The CT scan takes about 10 minutes. Once the CT scan is finished, the mask and bite tray will be removed.
Remember: You should have nothing to eat or drink for four (4) hours before the CT scan.
Step B: Fusion MRI
As part of the planning process, a fusion MRI scan may be needed. This MRI is like those you may have had in the past, but is used as part of the treatment planning. The images are closer together than other MRI’s you may have had. This gives us a more defined picture of the treatment area.
The Fusion MRI must be done at the UW Hospitals and Clinics because the scan needs to be fed into our computer in order to plan your treatment. At this time, we cannot retrieve scans done at other places. The fusion MRI may be done either on the same day as your first meeting with the doctor, on the day you have step one done or on a separate date. If you have never had an MRI before, please let the nurse know, so you can be given a handout that explains it in detail.
If you are claustrophobic (feel afraid in confined spaces) or have problems completing MRIs, please let your doctor or nurse know so that medicine can be ordered to help you relax. Please let the doctor or nurse know if you have any of the items listed below.
- pacemaker
- artificial heart valve
- defibrillator
- brain aneurysm clips
- implanted pumps or chemotherapy ports
- neurostimulators
- eye or ear implants
- stents, coils or filters
Treatment Planning
After the bite tray, face mask and head mold are finished, we will create your treatment plan. It takes about 7-10 days to complete the plan. It depends on the complexity of your lesion.
There are many treatment options depending on the type of lesion that you have. Most patients will receive daily treatments (usually 5 treatments per week) Monday through Friday for 5-7 weeks. Some patients may only be treated once or twice a week.
The first treatment takes about 60-90 minutes. This is due to the length of the set up process. The rest of the treatments take about 30 minutes.
Your doctor will discuss with you the exact treatment needed for your type of lesion.
During Treatment
While you are having treatment you will see your doctor or nurse once a week to watch for the side effects of treatment. If you have questions at any time during your treatment, please let the therapist know and he or she will arrange for you to meet with a doctor. During the last week of treatment you will meet with your doctor to discuss follow-up care.
Side effects
Most of the time there are few immediate side effects. The most common side effects are listed below.
- Skin irritation – Red, dry skin, like a sunburn, will occur in all patients with a tumor in the head or neck region and may occur in some patients with brain tumors. While you are having treatments we will check your skin, give you a cream and talk with you about ways to protect and maintain your skin.
- Hair loss - hair loss is often only small patchy areas on the head or face (often in the beard area)
- Fatigue - Many find that they are able to carry on their normal routines with little problem. Some find that they begin to feel more tired near the end of treatments and may need to rest. Taking rest breaks is very important. You will need to listen to your body and rest as needed.
- Thrush - You should inspect your tongue and the inside of your mouth daily. It should be pink and smooth. If you notice any red or white patches or develop a “funny or strange” taste in your mouth, please let your doctor or nurse know. Sometimes a yeast infection (thrush) occurs.
- Nausea and Nutritional Needs - Although rare, some patients may have nausea or vomiting during treatment. If you do, please let your doctor or nurse know, so medicines can be ordered for you. Nutrition is very important. Avoid alcohol and smoking. We do not want you to lose weight at this time. Try to eat three servings of protein and drink at least 6-8 glasses of water every day. Good eating and drinking habits will help lessen the other side effects. If you have further questions about nutrition please discuss them with your nurse. A dietician can help with any questions or concerns.
Side effects of radiation to the tumor area
You do not need to read both the brain and head and neck tumor side effects listed below. Read only the section that refers to the type of tumor you have.
Brain Radiation Side Effects
If your tumor is in the brain some of the side effects are listed below.
Brain swelling - A small number of patients may have brain swelling during treatment or weeks to months after treatment is over. If this occurs, you will be treated with a steroid medicine to reduce the swelling.
Symptoms ofbrain swelling can vary depending upon the location and type of tumor or lesion you have. If you have any of these, tell your doctor. A few of the more common things to watch for are listed below.
- Headaches that are not relieved by TylenolÒ
- Headaches associated with nausea and vomiting
- Numbness or tingling of the face, hand, arm or leg
- Clumsiness of a hand or leg
- Vision, hearing or speech changes or difficulties
- Balance or walking difficulties or dizziness
- New seizures or worsening of seizures
Head and Neck Radiation Side Effects
If you have a head or neck tumor some of the side effects are listed below.
- Sore throat and trouble swallowing - Many people will begin to have a sore throat a couple of weeks into treatment. As the throat becomes sorer, you may have trouble swallowing like a sore throat with a cold. Please let your doctor know so medicines can be ordered to help ease the discomfort.
- Dry mouth and loss of saliva - You will begin to develop a dry mouth around the same time as the sore throat because the amount of saliva you produce will decrease. Your saliva may become thick. Please let the doctor or nurse know about these symptoms because there are some things that can be done to lessen these effects.
- Dental care and Oral hygiene -The loss of saliva and dry mouth described above can have major effects on the teeth. Your doctor will discuss this with you in greater detail. It is very important for you to do a good job brushing your teeth.
- Taste Changes -Your sense of taste will change as you are going through radiation because taste buds are affected. Your sense of taste should return in a few months after your treatment is over.
Risks
Your doctor will discuss the immediate and long-term risks of this treatment with you. The risks vary from patient to patient and depend on a number of factors.
Questions or concerns
While you are having treatments, you will see your doctor or nurse weekly. If you have any questions at any time during your treatments, please let the therapist working with you know and they will arrange for you to meet with your doctor.
If you have any questions or problems, please feel free to call the Radiotherapy Clinic at 608-263-8500. If the clinic is closed, your call will transfer to the hospital paging operator. Ask for the radiotherapy doctor on call. Leave your name and phone number with the area code. The doctor will call you back.
If you live outside of the area, call toll-free by dialing1-800-323-8942.
The information provided should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Any duplication or distribution of the information contained herein is strictly prohibited.
Last Updated: 10/14/2009
Copyright © 01/23/2008 University of Wisconsin Hospitals and Clinics Authority. All rights reserved. Produced by the Department of Nursing. UWH #5485
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