You are not offending us, we are all guys right? Here is what I read on the internet "All prostate therapeutic treatments cause ED in 6 out of 10 men. Also, it always causes lack of ejaculation, but not lack of orgasm. ED can be treated with PDES inhibitors only if erectile nerves have been successfully preserved. Radiotherapy has a negative effect on erectile function (can't recall the web page for this but use a sentence as a search phrase and you'll probably find it).
Then there is this "So, it's erectile dysfunction. That's the big concern, and there's no evidence that the risk of erectile dysfunction from radiation has any difference between the different delivery methods (proton, IMRT, SBRT, brachytherapy) and if you look at actual risk, the way we gauge that, let's say for a 60-year-old, someone who isn't already using Viagra or Cialis, the chances of erectile dysfunction when you radiate the whole prostate (which is typically done) is probably about 1 in 3. And we're talking about a type of erectile dysfunction that DOES NOT respond to Viagra or Cialis. So that's sometimes a little confusing. The rest of the world thinks if you need Viagra or Cialis, then you have erectile dysfunction. In the prostate cancer world, if you have erectile dysfunction but it responds to Viagra or Cialis, that's not counted as erectile dysfunction. That's counted as you're NORMAL". In summary, "Whether you do brachytherapy, SBRT, proton therapy, the risk of erectile dysfunction is the same.”