I did get side effects from the radiation to the primary cancer in my prostate, which I had a few months later. They didn't emerge until a year after the therapy, and are annoying, but nothing that would have changed my decision if I'd known for sure in advance that I'd get them. That radiation was much stronger: 60 gy (vs 20). I had already talked with my oncology team and told them I wanted to treat the cancer aggressively, and they'd agreed to "throw the kitchen sink at it" — the radiation I got to my prostate was a so-called "curative" dose (even though my cancer isn't believed to be curable).