If it's any consolation, radiation is light-years better than it was even 10 years ago. I know five people who've had external beam radiation, for example, without damage or bad side effects or regrets. I think my concern would be whether a facility was using state-of-the-art equipment operated by very well-trained people. If it would help, consult first with the radiologist (M.D.) who would be doing it.

As to drugs, none of them are virtually without possible side effects. But tamoxifen has been used for a long time and the possible side-effects arebwell-known and can be watched for. I worry more about new drugs with glossy ad campaigns and teeny weeny print listing (only so far known!) side effects. Or TV commercials where they are stated at 200 times the ability of the human ear to understand.

But, yes, we still need some bad guys to fight a bad guy (cancer) but if aspirin alone would do the trick...well, science isn't there yet. A friend of mine pointed out that the only reason I had breast cancer is because I didn't die first as I would have in a previous century or a place without medicine to treat stuff that came before it. I have a darker sense of humor or just appreciate irony but it gave welcome perspective at the time.