Radiotherapy is only used if the benefits outweigh the risks. Your treatment team will discuss the risks of any radiotherapy procedures that are recommended for you.
Before having radiotherapy, you will be asked to sign a consent form to confirm that you agree to the treatment and understand any risks involved.
Treatment plan
Your treatment will be carefully planned to ensure that the radiotherapy destroys as many cancerous cells as possible, while affecting as few healthy cells as possible.
The amount of radiotherapy you have will depend on:
- where the cancer is in your body
- the type and size of the cancer
- your general state of health
In planning your treatment, a radiotherapist (radiotherapy specialist or clinical oncologist) will use all the information gathered during your diagnosis. They may also carry out some additional tests to find out more about the size and site of the cancer and to get a clearer understanding of the area of your body to be treated.
Once your oncologist has all the relevant information, they will calculate the total dose of radiotherapy that you need and the number of individual doses (fractions) required.
If you are having external radiotherapy, a simulator machine will be used as part of your treatment planning. The simulator moves in the same way as the machine that will be used for your treatment. It uses X-rays to take pictures so that the radiographer knows how to position your body when you have your treatment. A radiographer is a healthcare professional who is trained in taking X-rays.
Many patients will also have a computerised tomography scan (CT) scan to help the oncologist to target their tumour accurately.
After the exact area of your body to be treated has been established, the radiographer will put small but permanent ink marks on your skin to ensure that the same area is treated each time.
If you are having external radiotherapy to your head or neck, or if it is difficult for you to keep the part of your body having treatment still, a plastic mould will be made for you to wear during treatment. In this case, the ink markings will be made on the mould rather than on your skin.
You can read more about planning external radiotherapy on the Cancer Research UK website.
External radiotherapy
If you are having external radiotherapy, you will usually receive your treatment as an outpatient, which means that you will not have to stay in hospital overnight. You may need to stay in hospital if you are having chemotherapy in combination with radiotherapy (chemoradiotherapy), or if you are unwell.
During the procedure, you will be positioned on a treatment table and a radiotherapy machine (linear accelerator) will direct high-energy rays at the area being treated.
You will need to keep as still as possible throughout the treatment. The procedure only takes a few minutes and is completely painless. You will be able to breathe normally during your treatment.
While you are having treatment, you will be left alone in the treatment room. A radiographer will operate the machine from outside the room and will watch you through a window or on closed circuit television. If necessary, you will be able to talk to the radiographer during the procedure using an intercom.
Internal radiotherapy
Internal radiotherapy can be given as an implant, drink or injection. Depending on the type of treatment being used, you may need to stay in hospital for a short period of time.
Radioactive implants
If you have a radioactive implant or radioactive liquid, your hospital will have a number of safety guidelines in place to ensure that hospital staff and visitors are not exposed to radiation. Hospital staff will explain the safety procedures to you before your treatment.
Radioactive implants are placed into, or next to, the cancerous tumour so that it gets the highest possible dose of radiation. Although the area close to the implant will also get a high dose of radiation, other parts of your body will receive a very small amount of radiation which is not a risk to your health.
If you are having a radioactive implant, you may need to stay in hospital for a few days until the radioactive source is removed. After the implant has been removed, you are not a risk to others.
Permanent implants do not present a risk because they produce a very small amount of radiation that gradually decreases over time.
Liquid radiotherapy
After having liquid radiotherapy, you may be radioactive for a few days. This will not cause any long-term harm to your body, but you will probably have to stay in hospital until the radioactivity decreases. This is a precautionary measure to reduce other people’s exposure to radiation.
You will be able to leave hospital after the radiation has fallen to a safe level. Your treatment team may give you some safety advice to follow for a few days when you get home.
If there is anything about your treatment that you do not understand, or if there is anything you are unsure about, you should ask a member of your treatment team to explain it to you in more detail.
You can read more about internal radiotherapy safety on the Cancer Research UK website.
