Planning stereotactic radiotherapy
Planning SRT involves several steps.
You start with having a CT scan in the radiotherapy department. You may also have MRI scans or PET scans of the area of your body to be treated. The information from these scans feeds directly into the radiotherapy planning computer.
The radiotherapy team then puts together a treatment plan.
Your doctor makes sure that all of the cancer is inside the radiotherapy field. And they avoid as much healthy tissue as possible. This reduces the risk of side effects.
Skin markings
The radiographers might make marks on your skin that act as reference points. This is to make sure every treatment session is accurate.
Radiotherapy masks and moulds
If you have radiotherapy to your head or neck, you may need to wear a radiotherapy mask during your treatment. This is also called a shell or mould.
Most types of masks are made of a mesh material with lots of small holes. You can have a mould for other parts of the body, such as the breast or limbs.
The mould or mask keeps the treatment area completely still. This is so your treatment will be as accurate as possible.
Metal markers
You may have small metal markers (fiducial markers) put in or near your tumour. This is common for prostate cancer.
To place the markers, your doctor inserts a needle into the area of skin over the cancer. They do this while you are having an ultrasound scan. Once the tip of the needle is in the right place your doctor releases small gold pellets or rods.
Your radiographers can then see the markers on x-rays and scans while you're having treatment. They act as a marker for the treatment area, and makes sure that the treatment is very accurate. Your radiographers will take x-rays or scans every day before treatment if you have this type of metal marker.
After the planning session
You usually have to wait a few days or up to 2 weeks for your treatment plan to be ready.
You then get an appointment for your first session of radiotherapy.