Brachytherapy (radioactive seed implants) is sometimes used to treat small tumours of the prostate gland. It is carried out under a general anaesthetic, or sometimes a spinal anaesthetic. Small radioactive metal seeds are inserted into the tumour within the prostate gland, and they release small doses of radiation very slowly over a period of time. The seeds are not removed, but stay in the prostate tissue. The radioactivity gradually fades away over approximately a year. The radiation affects only the area a few millimetres around the seeds, so there is no danger of it affecting other people.