Radiotherapy is a common treatment for prostate cancer and many other cancers.
X rays were discovered by a In late 1895, the German physicist, Roentgen in 1895. He called his discovery X-rays because X is commonly used to denote the unknown. He experimented with taking pictures with these new rays (including one of the earliest X-ray photos in 1895 of his wife’s hand complete with ring – shown on right) and it wasn’t long before it was being used in medical diagnosis and then treatment. In 1899 there was the first reported cure due to radiotherapy and in 1922 radiation oncology was recognised as a medical discipline.
Radiotherapy works by damaging the DNA within the tumour cells and destroying their ability to reproduce – killing them in other words. Unfortunately it also kills healthy cells but these are more able to recover and repair themselves. The major challenge for radiation still remains hitting cancer cells with sufficient strength to effectively kill them whilst reducing as far as possible collateral damage to healthy cells.
There are two type of radiotherapy: external and internal.
External Beam Treatment (EBRT) is when a particle beam produced by a machine called a ‘linear accelerator’ is passed into the body from outside.
There are currently two major type of external radiotherapy; 3D Conformal Radiotherapy where the particle beam is made to ‘conform’ to the shape of the tumour and ’intensity modulated radiation therapy ‘(IMRT) which uses computer software to target cancer cells with high doses of radiation whilst sparing normal cells.
Radiotherapy is normally given over a period of 4 to 7 weeks in daily doses called ‘fractions’. The effects (and the side effects) or radiotherapy are therefore cumulative.
Side effects include fatigue, urinary pain, erectile dysfunction and diarrhoea.
An alternative to external radiotherapy is internal radiotherapy known as Brachytherapy. In this treatment, radioactive ‘seeds’ are inserted through fine needles directly into the prostate under anesthetic. This enables high doses of radiation to be delivered directly to the prostate without affecting surrounding structures. As a consequence the side effects tend to be less pronounced.
