I am sorry to hear of your diagnosis Sax. The shock, fear, and unknown are extremely overwhelming after the news. And I know exactly what you are feeling right now.
I was diagnosed with clear cell in the right ankle in October. I was shell shocked after the diagnosis, and it took a couple of weeks to sort it all out in my mind. I am a military veteran and fortunately was able to utilize one of the best VA hospitals in the country. I had a University Ortho Surgeon assigned to me who was absolutely wonderful. After we discussed the option of limb salvage and all the following reconstructive surgeries as well as the increased possibility of metastisis, I asked him a simple question. "If it was YOU sitting in this chair what would you do?" He didnt miss a beat and replied "I'd have the amputation". I accepted it completely and I had a below the knee amputation on Nov 13th. Was in the hospital for 4 days and off my pain meds in 3 weeks. Was it easy? No. Did it completely change my lifestyle? Absolutely. Did it save my life? Probably. I will say it was not as painful or traumatic I as I had envisioned in my fearful mind. I was on crutches 2 days after the surgery.
I am 7 weeks post op and am already walking on my prosthetic. You will learn that the changes in your lifestyle will be quickly overcome, and you will be surrounded by people to make your transition as easy as possible. I feel it was a small price to pay, at 46, to ensure I have more time to enjoy life and my beautiful wife.
Second opinions are always good. I personally did not feel the need to seek one out. As for knee replacement in lieu of amputation I would mention this. Alot depends on obtaining clear margins in order to ensure you are cancer free at the site. It was explained to me that "local reoccurence" is extremely likely after excision versus amputation. You would also run the increased risk of at least regional metastisis, which often times in distal extremities means the lymphnodes in the groin area. Not good.
Im not sure what the "NHS" system is, but I know I obtained a top of the line prosthetic from the VA, through a vendor that works with the Irag and Afghan amputees. I will be golfing and water skiing by this next summer. So I can tell you that there are prosthetics out there that allow you to live an active and productive lifestyle.
The MOST important thing to a fast and complete recovery is to stay POSITIVE. Don't let it beat you emotionally or in your head. If you can do that, the physical stuff can be overcome with determination, the support of your friends and family, and hard work. Don't be afraid.......you CAN do this.
My prayers and with you, and God Bless