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- Planning the EBRT treatment
Planning the EBRT treatment
EBRT needs to be carefully planned to ensure that enough radiation reaches the cancer, while as little radiation as possible reaches healthy tissues and organs. The planning steps below may take place over a few appointments.
Visit targetingcancer.com.au/radiation-therapy/ebrt to watch a video explaining how radiation therapy works. You may find that things are done slightly differently where you have treatment.
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Consultation session
- May take up to two hours.
- To assess whether radiation therapy is the right treatment for you, the radiation oncologist will talk to you, do a physical examination, and look at all your test results and scans.
- The radiation oncologist will explain how radiation therapy will help you, what will happen during planning and treatment, and what side effects to expect.
- You will also meet the radiation oncology nurse and a radiation therapist. They can provide support and further information. They will usually explain what side effects to expect and how to manage them.
- The radiation oncologist may arrange further x-rays, scans or other tests to find out more about the cancer.
- Consider taking someone with you to keep you company, ask questions and make notes.
CT planning session
- You’ll have a planning CT scan even if you had a CT scan to diagnose the cancer. It shows where you need to receive radiation. The CT planning or simulation scan is usually done soon after the consultation session.
- You will have the CT planning scan in the same position you will be placed in for treatment.
- You might have an injection of dye to help show up certain parts of your body.
- You may need to hold your breath during the scan. You may also have a special CT scan, called a 4DCT, to track your breathing or be taught how to take deep breath holds. This may improve treatment accuracy and helps protect the heart.
- The images are sent to a computer. This allows the radiation oncologist to work out where to direct the radiation. The oncologist will prescribe the dose of radiation to help the radiation therapists and medical physicist plan treatment.
Helping you to keep still
- You will usually need some type of device to help you stay in exactly the same position for each session and to keep you still during treatment.
- This is known as an immobilisation device. It will be made during the CT planning session. Depending on the area being treated, the device could be a breast board, a knee or foot cushion, or a bag that moulds to the shape of your body.
- For radiation therapy to the head or neck area, you may need to wear a plastic immobilisation mask. This will be made to fit you. A mask can feel strange and confining, but you will still be able to hear, speak and breathe.
- Depending on the area being treated, a device known as a spacer may be inserted to move normal tissue away from the area receiving radiation. Examples of spacers include gels and balloons.
Skin markings
- To make sure you are in the same position each session, a few very small permanent ink spots (tattoos) may be marked on your skin. These tattoos are the size of a small freckle and can’t be easily seen.
- Sometimes temporary ink marks are made on the skin. Ask the radiation therapist if you can wash these off or if you need to keep them until the end of the treatment. The ink may be redrawn during the course of treatment, but it will gradually fade.
- If you have to wear a mask or cast, the markings may be made on this device rather than on your skin.
- To help with image-guidance, you may have a small surgical procedure to insert markers (usually made of gold) into or near the cancer. These internal markers can then be seen on scans during the treatment.
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More resources
Prof June Corry, Radiation Oncologist, GenesisCare, St Vincent’s Hospital, VIC; Prof Bryan Burmeister, Senior Radiation Oncologist, GenesisCare Fraser Coast, Hervey Bay Hospital, and The University of Queensland, QLD; Sandra Donaldson, 13 11 20 Consultant, Cancer Council WA; Jane Freeman, Accredited Practising Dietitian (Cancer specialist), Canutrition, NSW; Sinead Hanley, Consumer; David Jolly, Senior Medical Physicist, Icon Cancer Centre Richmond, VIC; Christine Kitto, Consumer; A/Prof Grace Kong, Nuclear Medicine Physician, Peter MacCallum Cancer Centre, VIC; A/Prof Sasha Senthi, Radiation Oncologist, The Alfred Hospital and Monash University, VIC; John Spurr, Consumer; Chris Twyford, Clinical Nurse Consultant, Radiation Oncology, Cancer Rapid Assessment Unit and Outpatients, Canberra Hospital, ACT; Gabrielle Vigar, Nurse Unit Manager, Radiation Oncology/Cancer Outpatients, Cancer Program, Royal Adelaide Hospital, SA.
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