Your first planning visit will take 30–60 minutes. The staff in the radiotherapy department will explain what to expect. They will tell you beforehand if you need to prepare in any special way. For example, you may be asked to drink plenty of water. It‘s important for you to feel that you’re involved in your treatment, so feel free to ask as many questions as you need to.
You’ll usually have a CT (computerised tomography) scan taken of the area to be treated. This helps your doctor and physicist plan the precise area for your radiotherapy. Before your scan, you may be asked to remove some of your clothes and to wear a gown.
The CT scan takes lots of images from different angles to build up a three-dimensional picture. You may have an injection of dye into a vein when you have the CT scan. This allows particular areas of the body to be seen more clearly. You may also be asked to have a full bladder for the scan.
Instead of a CT scan, some people have an MRI (magnetic resonance imaging) scan or occasionally a PET (positron emission tomography) scan to help with planning their treatment. An MRI scan uses powerful magnetic fields to give a very detailed picture of the area that needs treating. A PET scan uses low dose radioactive glucose (a type of sugar) to measure the activity of cells in different parts of the body. Your hospital team will tell you more about these scans.
During your scan, you’ll need to lie still on a hard couch. If you feel uncomfortable when the radiographers position you on the couch, let them know so that they can make you more comfortable. This is important because, once you’re comfortable, the details of your position will be recorded. You’ll need to lie in the same position on a similar couch for your treatment.
The information from the scan is fed into a planning computer, which will be used by your radiotherapy team to work out the precise dose and area of your treatment. It can take up to two weeks to plan your treatment.
The radiographer may need to make some small marks on your skin. This is to help them position you accurately and to show where the rays will be directed. These marks must stay visible throughout your treatment, and permanent marks (like tiny tattoos) are usually used. These are extremely small, and will only be done with your permission. It may be a little uncomfortable while they are done.