General side effects of radiotherapy
A person undergoing radiotherapy to kill cancer cells will usually experience some side effects. The types of side effects and how severe they are vary between different people, so it is difficult to know how radiotherapy will affect an individual person.
The higher the dose of radiation, the more chances there will be that a patient experiences side effects, so the radiotherapy team will use their expertise in providing treatment designed to kill the cancer in a patient but with the fewest possible side effects.
The side effects caused by radiotherapy will depend on:
- The type of radiotherapy used – such as external radiotherapy from outside the body or internal radiotherapy given within the body – and it's dosage, or how much is used
- The part of the body that's being targeted – for example, some of the side effects from treating lung cancer will be different to those from treating bowel cancer
- The person's general health and ability to heal.
While some patients might experience only mild side effects, others with similar treatment will have more severe side effects. Before beginning radiotherapy the members of the radiotherapy team should discuss with the patient the possible side effects and help in preparing for and managing them.
The side effects are often classed as early or late. Early side effects generally occur during treatment and end within a few weeks afterwards. Late side effects either begin during or shortly after treatment and continue for at least 6 months afterwards – this type is also called long-term and can be permanent – or they can appear months or years after treatment has ended. The more common general side effects are discussed below.