As Elodie said, I have had an amputation to take care of my synovial sarcoma and would be more than happy to talk to you about anything you want to know.
To answer your immediate questions though:
1) I do not and never have regretted my decision to get an amputation. My amputation is above the knee, which is much more difficult than below knee, but I still do not regret it. When we amputated we got incredible margins and now I am a year and a half out without any sign of cancer returning. I took the full measure to maximize my chances of survival and it looks like that decision has paid off. I also know that if I had tried the limb salvage and cancer had returned, I would have always questioned if I had made the right decision. However if the cancer ever comes back now, I know I did everything I could do right from the start and it was just bound to return.
2) I talked to 5 different surgeons. 3 said they would try a limb salvage and then amputate if the cancer came back. 2 said amputate. I didn't want to roll the dice with my life so I went ahead and pulled the trigger.
3) Since the day of my amputation I have been 100% cancer free, so yes, I would say that it benefitted me!
4) Phantom limbs are very different than phantom pains. Phantom limbs are actually beneficial when wearing a prosthesis because it makes it feel like your leg is there. Right now, sitting here typing, the inside, bottom of my foot, my heel and my big toe are tingling. I can also feel my calf. It's definitely an interesting experience and kind of impossible to totally explain unless you have felt it!
Phantom pains can be brutal. I had very severe phantom pains that started shortly after my amputation. They put me on all sorts of drugs to try to stop them, including Lyrica and Neurontin. Nothing touched them. But then I read about mirror therapy. Basically you trick your brain into thinking your leg is still there and it will mold your foot the way you want it to be and stops the phantom pain. It's truly amazing and I have recommended it to a number of other new amputees who have confirmed that it worked for them as well. I wrote a post about it that you can see here: http://survivingsarcoma.com/?p=987
5) I did 5 rounds of very intense chemo and 25 days of radiation. Since I got the amputation, I don't know that it was necessarily worth burning my leg up with that stuff, but at the same time, I would probably do it again. The way I look at it is that all of these things are killing the cancer cells, and that is exactly what I wanted, as much stuff attacking those cells as possible.
If there is anything else you want to know or want to talk about feel free to shoot me an email at ■■■■■■■■■■■■■■■■.
I hope you can make peace with your decision and whatever you decide, go at it with confidence that you are doing the right thing!