Types of radiotherapy
Posted on 12/01/2011
Radiotherapy can be given in two ways. It can be given from:
· outside the body (external radiotherapy) - using X-rays, small particles called electrons or, in rare cases, other particles such as protons; external radiotherapy is usually given once a day as a course of treatment over a number of days or weeks
· within the body (internal radiotherapy, also known as brachytherapy) - either by drinking a liquid that is absorbed by the cancerous cells or by putting radioactive material into, or close to, the tumour, usually for a small number of treatments (brachytherapy) or by injecting or drinking a liquid that is absorbed by the cancerous cells - for example, radioiodine for thyroid cancer
Courses of radiation
Radiotherapy is usually given as a course of treatment that lasts for a number of days or weeks.
Most people who have radiotherapy to treat a serious condition, such as cancer, have five treatments a week with a break at the weekend. Taking a break allows the normal, non-cancerous cells to recover.
In some cases, treatment may be given more than once a day or over the weekend.
Fractions
Radiation treatment is divided into a number of small doses called fractions, which are usually given over a number of weeks. Fractions are used to reduce the side effects of a full dose of radiation. The number of fractions required will depend on the type of cancer being treated.
Combination therapy
Radiotherapy is often used in combination with other treatments, such as chemotherapy (powerful medication that is used to treat cancer). This is known as chemoradiotherapy.
Chemoradiotherapy can be used to try to cure a cancerous tumour, to shrink a tumour before it is removed using surgery, or after surgery to reduce the risk of relapse.
