radiotherapy effects for SLE sufferer

hello

is anyone out there aware if the effects of radiotherapy to the head and neck area are affected if you have SLE - this is systemic lupus whihc I was diagnosed with in 1996.  I was treated with a type of chemo at the time and after an acute period of about 9 months I was in remission for quite a few years.  I took steriods for about 7 years but had very few flare ups of the disease except periodic problems with swollen fingers.

I have just started RT to my neck and back of throat and am very nervous in case the side effects of RT - bad at the best of times - may be harder for me to tolerate due to the fact that I have SLE which is an auto-immune disorder, which amongst other things, can often affect a person's mouth. 

any news would be most appreciated if anyone knows about this, or indeed if any of you have also had SLE

many thanks Suzy