Also known as: External Beam Radiation Therapy
External beam radiation therapy (EBRT) is a type of cancer treatment that helps reduce the size of tumors through precise doses of X-ray beams.
The most common type of radiotherapy, EBRT uses different imaging techniques and a dedicated computer-controlled radiation machine (linear accelerator) to administer doses of carefully regulated radiation.
The radiation helps eliminate cancer cells and reduce the size of tumors but can also affect healthy organs surrounding the cancer. This is why radiation has various side effects.
Fortunately, different types of EBRT exist. These different treatments help reduce the risk of radiation exposure to healthy tissue by adding layers of precision and accuracy to your personal treatment plan. These different types of EBRT include:
- Image-guided radiation therapy
- Intensity modulated radiation therapy
- 3-D conformal radiation therapy
Because EBRT is administered over several short and pain-free sessions, you will first undergo a variety of scans and procedures to help determine how doctors will best treat your specific situation.
These possible tests include CT, PET and MRI scans and are used to pinpoint the exact location of the tumor. The tests are the first step your team of oncologists and caregivers takes in constructing your personalized treatment plan.
As your IMRT treatment begins, calibration and diagnostic procedures are put in place. These may include a body mold and small freckle-sized tattoos. The tattoos help the radiation equipment align to the targeted area, and the body mold comfortably assists you in maintaining a still position on the treatment table while receiving radiation.
These procedures are calibrated on a daily basis to ensure precision, accuracy and consistency throughout each therapy session.
Each radiation therapy session runs like a CT or MRI scan. Your radiotherapist positions you on the treatment table surrounded by the medical linear accelerator. Once the machine is ready to deliver the radiation, your radiation therapist will exit the room.
At Providence, we care about providing comfort, so in situations like these, your therapists will maintain contact with you over a microphone and intercom at all times should you need anything.
Each session is short and pain free. In fact, the external radiation beam is only on for a few seconds during your session. Most of the time is used to position you on the treatment table, to ensure consistent accuracy of the beam on your body.
The most important risk to be aware of is the fact that your body is being exposed to short bursts of radiation. Fortunately, with the advancement of state-of-the-art cancer treatments, doctors are able to accurately target tumors while minimizing radiation exposure and sparing vital adjacent organs.
The radiation itself can also lead to certain side effects. Reactions to radiation can include dryness or itching of the skin over the target, soreness and nausea.
How is radiation administered?
Radiation therapy is administered either externally, by using a machine that generates a radiation beam, or internally by placing radioactive material into body tissues or cavities.
What happens in external radiation therapy?
The equipment used for the external beam therapy is called a linear accelerator. The patient lies down on a treatment table and is placed under the machine. The machine does not touch the patient. A linear accelerator is capable of rotating 360º around the patient. The physician will, through the treatment planning process, prescribe the direction in which the X-ray beam is aimed. For very select cases, especially skin lesions, superficial X-rays may be used. The physicians will select which machine is appropriate for your circumstances.
What exactly is a linear accelerator?
In very basic terms, the machine is named a linear accelerator because of the nature of how the X-rays are generated. A stream of high-speed electrons is accelerated down a linear path until it comes in contact with a target. Then, X-rays are produced. In addition to X-ray production, our linear accelerators have the ability to move this “target” out of the way and produce electrons as a means to treat patients. The difference between using X-rays and using electrons for treatment is the depth with which they are able to penetrate. Cases such as skin cancers would be an example where electrons would be used.
What happens during my first visit after consultation?
Please arrive and be seated in our waiting room. You may wait until you are greeted by the radiation therapist to change your clothes. At the time of your scheduled appointment, a therapist will step into the waiting room and explain the process for changing your clothes and storing them securely in a locker. During this appointment, your simulation will take place. A simulation is the process in which the radiation area will be targeted and marked. You will be placed in a position that will be reproduced each visit. This positioning is very important to your daily treatments and the accuracy with which we deliver the treatment. Our goal is to place you in the perfect body position where the target area may be accessed yet be comfortable enough for you to hold still. This requires the direction of the radiation oncologist, the radiation therapist and sometimes the radiation physicist/dosimetrist. The simulator room is a specialized X-ray room where images are acquired for both calculation and documentation purposes. This tends to be longer than your treatment appointment.
What happens during my treatments?
You may go ahead and change into a gown in the same fashion you did during the last visit. Lock your clothes into a locker and put the key around your wrist. A radiation therapist will come into the waiting room and escort you to the treatment room. Now you will be placed on the treatment table in the same position that was used in the simulator room. The therapists will use the markings and tattoos you were given to properly align your body. Once you are positioned, it is very important that you remain as still as possible and breathe normally.
X-ray films are taken initially in the treatment room to document and verify that the targeted area is aligned exactly as the physician prescribed. Once the physician approves these films, they are repeated weekly throughout your treatment as part of our quality assurance program to ensure you are receiving the highest-quality care.
The therapists leave the room during your treatment but are monitoring you both visually on a closed circuit TV monitor and audibly through an intercom system at all times.
During your treatment you may hear the sounds of the machine and see a red light flashing. They merely indicate that the equipment is on.
At the end of the treatment, the therapists will assist you off the treatment table. Please do not attempt to get up and exit by yourself. It is important to continue to hold still until the therapists inform you your treatment is complete and that you are finished.
How long will my daily treatment take?
Your normal daily treatment length will be from 15 to 30 minutes depending on the complexity of your set up. Most treatments are routinely given Monday through Friday, once per day. There are exceptions to this routine, which are dictated by the physician’s prescription.
How many treatments will I need?
The radiation oncologist writes a prescription that will include the daily dose of radiation, the type/energy of radiation, how many fractions (or days) per treatment and the total dose. There are many factors the physician needs to take into account when writing the prescription such as the pathology, tumor volume, surrounding normal tissue tolerance, concurrent chemotherapy or other treatments, etc. By delivering the treatments over a period of weeks, the normal tissues have a chance to recover more readily and tolerate the total dose better. An average course of treatment would be six to eight weeks.
Can I miss a treatment?
To receive the maximum benefit from therapy, it is essential that you receive all your prescribed radiation treatments. If you think you cannot report for a scheduled appointment, please call the nurse or therapist. Missed appointments are made up so that you may still receive the same total number of treatments prescribed. We will make every effort to help you in making all of your scheduled doctor’s appointments. We are very familiar with patients who have to see more than one physician in a day, and we will make every effort to reschedule your appointment if necessary so that you may do so.
Sometimes your radiation oncologist may prescribe a treatment break. This allows normal tissues a chance to recover from the effects of radiation.
Does the treatment hurt?
Radiation treatments do not hurt at all. The treatment is painless.
Will I become radioactive after I receive my external radiation treatment?
No. Neither you nor your clothing will become radioactive, and it is perfectly safe for you to be around your family and loved ones.
Will I experience side effects from treatment?
Any side effects you may experience depend upon the amount and frequency of radiation and the anatomic area that is treated. Side effects vary from person to person due to individual sensitivity to radiation.
Before treatment begins, the radiation oncologist and nurse will discuss with you any side effects that may occur and what you can do to control or relieve them. It is important to remember that most side effects are temporary. They generally subside within a few weeks after treatment, although some may take a little longer to resolve. Most patients experience fatigue at some point during the course of therapy. It may persist for a few weeks after the completion of treatment. Please remember, fatigue is a usual side effect of radiation and is not an indication of progression of disease. Lay people commonly believe that nausea, vomiting, diarrhea and hair loss are universal side effects from radiation. Nausea, vomiting, and diarrhea may occur when the abdomen is radiated. Hair loss will probably occur to the area of treatment. Scalp hair or beard will likely fall out if the scalp, mouth or throat is radiated. The size of the radiation field and the dose of radiation determine whether you will have these side effects. Radiation side effects are localized and pertain only to the radiated area.
What should I do if these reactions occur?
Report any reactions to the radiation oncologist, nurse or therapist before your treatment. There are many comfort measures and medications available to relieve these side effects.
Will radiation affect my skin?
For the first couple of weeks of treatment, you are not likely to notice any changes. Then you may notice that the skin exposed to the radiation may become red, dry and itchy. These skin changes are temporary and will heal a few weeks after radiation is completed.
Recommended care of skin exposed to the radiation beam at its entrance point and its exit point:
- Keep the irradiated skin clean and dry. Cleanse with a mild soap and water. Use your bare hand to cleanse the area. You can judge the sensitivity and pressure better this way. Gently pat the area dry. Avoid vigorous rubbing, massaging or scratching.
- Avoid wearing tight clothing that could rub, chafe or otherwise irritate your skin. Cotton fabrics are better than synthetics next to your skin.
- Do not use heating pads, heat or sun lamps, hot water bottles or ice packs on the treated areas.
- Do not expose the treated skin to sun. Wear protective clothing over the treated area. Sunscreen does not provide enough protection.
- Do not apply deodorants, cosmetics, lotions, powders, petroleum jelly, products containing alcohol, or products such as Deep Heat®, Icy Heat® or Tiger Balm® to the irradiated skin. If you have any questions, please ask the nurse or therapist for clarification.
- Do not apply vitamin E oil or cream to the irradiated area. Only apply the gel or cream we provide.
Are there any restrictions on my activities?
You are encouraged to carry on your normal daily activities as much as possible, as long as you are not feeling overstressed. However, depending on the area of the body that we are treating and whether you have additional treatment modalities such as surgery, you may need to discuss restrictions with the physician.
Many people continue to work without experiencing adverse effects. If you feel you cannot continue to work or need a reduced schedule, please talk to your physician or nurse. Try to balance your daily activities with periods of rest, if necessary.
Do I need to follow a special diet?
Depending on your specific treatment area and side effects, you may need to modify your diet. In general, you should eat a well-balanced diet that is high in protein and calories. A high-protein, high-calorie diet will help you maintain your weight and will provide the nutrients necessary for normal tissue to recover. We will make arrangements for you and/or a family member to meet with our registered dietitian when appropriate.
Will extra vitamins help?
When feeling tired, many people want to take vitamin supplements. We advise our patients not to take antioxidants, such as vitamins A, C, and E, selenium and beta-carotene. Radiation is an oxidant, and we are concerned that taking extra antioxidants concurrently with the radiation may decrease the effectiveness of the treatments. Although one multivitamin tablet per day is permissible, we recommend that you do not take anything in addition to that.
What about driving?
Radiation is usually given on an outpatient basis, and most people are able to drive themselves to therapy. In some cases, you may need to arrange for a friend or relative to drive you.
Will I be treated on holidays?
The department is usually closed on national holidays. However, in cases where this would negatively impact the effectiveness of the treatments, special arrangements are made for treatment on holidays.
Why do the hospital and radiation oncologists bill me separately?
The law requires all charges from hospital-based physicians, such as radiation oncologists, be issued separately. You should expect to receive several individual statements after your treatment is completed.
These charges cover many aspects of your care, such as consultation, treatment planning, administration of treatment, and follow-up visits.
Most insurance plans cover the cost of radiation therapy. If you have any questions, please contact our financial counselor.
After your course of treatment is completed, your radiation oncologist will schedule an initial follow-up visit within two to four weeks. At this time you will be examined to ensure that any side effects are resolving.
Every effort is made to minimize the side effects of radiation by excluding normal tissue from the treatment field. Your radiation oncologist is trained in recognizing and treating these effects promptly.
To ensure your continued health, future follow-up visits will be scheduled every three to six months. If another cancer physician is also monitoring you, your follow-up schedule will be adjusted for that.
Your primary physician or medical oncologist may have questions about changes in your physical examinations brought about by the radiation therapy treatment. Since these changes can be subtle and progress months or even years after treatment, it is important that you adhere to your follow-up appointment schedule. Your radiation oncologist can work with your primary physician to avoid unnecessary diagnostic procedures.