Internal radiotherapy implants are radioactive metal wires, seeds, or tubes put into your body, inside or close to a tumour. The radioactive metal is called a source and is left inside the body for a period of time. In many types of cancer the source is taken out after a few minutes.
In some types of cancer, small metal implants, or seeds, are left in the body permanently. These implants are made of radioactive gold or contain radioactive iodine. They give a very high dose of radiation to the area of the cancer cells. For most types of implants the radioactivity only travels a few millimetres through body tissue and so it can’t be detected outside the body.
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