I had RP (Feb 2015). Brother just dx is having RT (9 x 5 sessions)
Both dx is very similar - please see my profile. Others have answered your original question. My input :
1. AS is not an option at Grade 4 and your young age of 67 assuming you have no other life limiting issues
- I would aim to make a decision within 2 months. You may already have
2. re. RT v RP as Chris and other experienced posters have said - nothing can be predicted. I was dry immediately and maybe an exception. Must be down to skill of surgeon, Kegels, luck or a mixture of all. I was asymptomatic and I had good bladder control pre op. I was only 59. ie I wasn't getting up at night like my brother had been.
3. ED - surgery . There will be exceptions, however body will take time to recover (this is major surgery whether open or lapro.) tissues are cut, traumatised. No ejaculate, as you know, possible. Body will recover albeit slowly and see other posts, plenty of options.
Do ask about Nerve sparing(NS) ? (I had Non .. ie NNS)
ED - RT - see other posts.. seems the 'negatives' occur further down the journey and slower , again unpredictable. Everyone is different.
You could explore other options - ie physical destruction / laser ablation in 'situ' ? However this is probably for single lesions (have you had a mpMRI and know where the lesion or lesions are located ? ) Possible need to be done private (See Clare / Claret posts)
Take advice from your MDT team, it may come down to your 'gut feel and attitude' to Surgery or RT. Obviously there are variants of RT you can explore - ie in very basic terms differing strengths v differing time periods. My RP was quite pain free and over night stay.