A close friend, and one of my golf partners, is a very youthful and fit 76. After his diagnosis he met with two urologists who would not do surgery. He finally found one who said yes he would do surgery, but he too recommended radiation.
He eventually decided on the radiation and is completing a 9 week course of treatments next week. He says, things are going well.
I don't know if was just his age or the fact he had prior prostate problems, but most seem to avoid surgery on older men. in my case at age 65, surgery was all they wanted to consider.