CMOT, are you around? Radiotherapy question..

[nightcat]

Hi CMOT
Following on from my earlier thread about my Dad's skin cancer and radiotherapy.. you said that the side effects associated with deeper radiation wouldn't perhaps apply in treating skin cancer, but I am trying to understand about treatment around the eye/head: is there a risk of damage to the brain?

How can the rays not be going right through the head if from what I read about radiotherapy in eg breast cancer, there has been a mention of burns/darkening/fibrillation of body tissue on the underside of the treated side...?

Is there really a way of avoiding a damage to deeper tissue - if so, how is this done?

My dad will be having some prep work done in the next few weeks, but I am still not clear on all this. If there is a risk of damage to the brain, then I think he would decline the treatment.

There seem to be a high success rate with basal cell cancer and radiotherapy in literature, but I am unable to find much on side effects of the radiotherapy and I don't know whether it hasn't been selectively ommitted..
We haven't yet been able to ask drs all the questions, another appt next week.

If you can add more on this I would be very grateful.

Hi Nightcat. With superficial x rays (which would be the type normally used for bcc/scc skin cancers) they are much, much lower energy than those used for breast (or indeed anything but skin) radiotherapy - approx 40 times lower. So with breast, the maximum dose of a beam is about 1 cm below the surface, for skin it is 1mm - and usually a layer is put on the skin to make the maximum be at the surface. By 5cm below the surface, there will be less than 10% of the radiation left, as opposed to more like 80% in the other type of radiotherapy.

So, there is no risk of brain damage with sxr as there is just very little radiation left by there

thank you CMOT, I really appreciate your help