Hello Thomas,
My situation sounds a lot like yours but I am about
6 months further along. I had my surgery in June of last year and like you my Gleason score went up from 7 to 9 (4+5) between my biopsy and my post-op pathology. I also had positive margins and I did adjuvant radiation (IMRT) and am on two years of hormones to make the radiation more effective in killing the cancer.
I am a lot older than you are but even at the astonishing age of 60 I am not ready to throw in the towel. I am determined that there will be sex after prostate cancer. Here are some of the challenges I am facing that you may face, too:
You didn't mention how many nerves were spared in your surgery. Since you are getting some reaction to Cialis at four months after surgery I expect that there was at least some nerve sparing. That is good. It means the nerves are starting to recover.
The bad news is that before the nerves have time to recover completely they will be zapped with radiation. That reduces the probability that they will ever recover completely. But it still can happen. It is possible (but not likely) that you will recover enough that you won't even need pills. It is also possible that you will recover enough that you will be able to get erections with the pills but not without.
If the pills don't work for you then you need to fall back to the next line of defense -- pumps and injections. These can be used to keep your erectile tissues working and to have sex even if the nerves never recover. There will still always be hope that the nerves will kick back in (they continue to recover for four years or more, especially with young guys like yourself). But while you wait for the nerves to recover you need to keep the machinery working and you will want to have a sex life. You should ask your doctor about
intercavernosal injections (ICI) and a vacuum erection device (VED). I inject a drug mixture called Trimix three times a week and use my VED on the other four days of the week. I am doing this for penile rehabilitation, mostly, since I don't currently have much of a sex life. Which brings us to the next problem you will face: hormone therapy.
Along with the radiation they will give you to kill any remaining cancer cells (has it started yet?) they will also give you hormone therapy to reduce you testosterone levels to keep the cancer from recovering from the radiation. I am doing a total of two years of hormones but you may do more or less depending on your doctor. Hormone therapy usually causes erectile dysfunction while a man is on it (and for six months to a year afterwards as he recovers). While you are on the hormones it will be hard to tell if your nerves are recovering or not. You will most likely need the pump or the injections to get erections. You will also have less libido (less desire for sex) and using the pump or the injections will be even less fun than it would be otherwise. But, since you are a young guy you want to keep you equipment working so you will want to stick to some sort of rehabilitation plan while you are on the hormones.
The chances of something I described above working for a guy your age is well over 90 percent. So that answer to your question about
"getting your erection back, even with drugs" is yes, you can. The bad news is that the when you said "drugs" you were probably thinking "pills" and the chances are that pills won't do it for you and, at least for a while, the "drugs" may have to be injected into your member.
Talk to your doctor about
all this. He can fix you up. It doesn't have to be over unless you give up.
Here are some videos you can watch that will tell you more about
this stuff. They are a lecture that was given by Dr. John Mulhall of the Sloane Kettering Memorial Medical Center in NY in 2007.
youtu.be/OQlGVT7HiF8 part 1 18:33
youtu.be/o7GmTZITJ5s part 2 15:20
youtu.be/ie8NkOu2VNA part 3 31:20