Question: What is the main danger when using radiotherapy on a patient?

Rob Brass answered on 13 Jun 2016:

Good question!

There are actually quite a few dangers! As far as the patient goes, we may have made a mistake while planning the treatment which could result in an overdose, causing nasty side effects or even death, or an underdose meaning we dont treat the tumour properly. Because we know of these dangers though we have lots of checks in place to make sure everything is spot on before we treat. We could also put the patient in the wrong place on the treatment couch and treat the wrong bit, this has happened in lots of radiotherapy departments although it is very rare. If it happened then its like a double whammy, we’d miss the tumour and so the treatment wouldnt be as effective and we’d also give a dose to healthy tissue. Thankfully, as we deliver in 15 – 35 daily treatments, if a mistake was made during 1 of them then its not as significant as its only 1 out of ~20.

There are lots of built in checks on the machine called ‘interlocks’, these are like switches that have to be closed before we can deliver any radiation. So the machine wont work unless everything is safe.

There’s also a danger to staff or visitors if they were to walk into the room while the beam was on. To stop this we dont have any doors at the entrance to our rooms, we have a short twisty corridor with a series of laser beams across the entrance. If someone breaks one of these beams while the beam is on then it’ll shut off!