Radiotherapy Frequently Asked Questions

If everything is so safe, why does everyone leave the room when I'm having my treatment?

Although the radiation beams are tightly focussed on the part of you we want to treat, there is always some radiation scattered around the room when the treatment machine is switched on. For you, set against the high dose we are giving your tumour, this low dose scattered radiation doesn't really matter. The radiographers and other staff work with these machines, all day, every day, year in, year out. Over a lifetime's work, they would, if they stayed in the room with every patient being treated, accumulate a significant radiation dose. Enough, perhaps, to cause genetic damage or even cancer.

If radiation causes cancer, why do you use radiation to treat cancer?

There is a paradox here. Low doses of radiation, such as those from the environment, are more likely to cause cancer than much higher doses. Low doses damage the instructions (genes) that cells contain. The cells survive the radiation and the faulty instructions are passed on through the generations and a cancer can form. High doses of radiation, such as those used in treatment, cause so much damage to the cell that it dies: there are no more generations, no cancer can develop. The key here is that, in both instances, radiation is damaging cells. We use radiation to treat cancer because it is an extremely effective way of killing cancer cells. It is also an effective method for treating cancer, provided we limit any damage to normal cells to the absolute minimum.

Will I glow in the dark?

No, but you can joke about it.

Will I be radioactive?

Not after external beam radiotherapy.

Does the treatment hurt?

No, you don't feel any more during treatment than you do having a chest x-ray done. There is no pain. The treatment couch is hard, to make sure that your position is constant during treatment, and so you may be a little uncomfortable. If you are being treated in a shell this may also be a bit uncomfortable.

Why do the machines keep breaking down?

These machines are highly complex pieces of technology. They also have a large number of safety features to make sure that exactly the right dose of treatment is given. Many problems with machines are, ironically enough, often caused by the safety features. A warning light comes on when there is nothing actually wrong. We can't just ignore these faulty warnings, we take them seriously and we will not use any machine that is not working absolutely perfectly. This may be also be a vocabulary problem. We talk, amongst ourselves and to patients of "machine breakdowns". We know what we mean, but the patients are likely to take a quite different meaning: imagining the machine to be a smouldering mass of melted metal and plastic emitting the occasional spark. Pilots are well aware of the psychology here. Why aren't we? As the plane aborts take-off during a thunderstorm the pilot doesn't come on the intercom to say "Sorry about that, but the plane broke down as we were trying to take off, we'll just take a few minutes to fix it and then try again". She says something along the lines of "Well we have a little problem with a warning indicator, the light seems to have jammed on, we'll take a few moments to check it out and then we should be on our way".