I've had to deal with it once. Are you willing to deal with the costs? It is fairly expensive.

Our last GS was the same age when he came down with Lympho Sarcoma. The vet gave us the options and one of them was a Chemo treatment that was aggressive and fairly new in the application. He was giving us a fair assessment stating this was not a given cure at his age, but if he showed promise within 24 hours, we would continue. He did good for 48, then his body and age caught up. We had to euthanize for his welfare.

I would see what your vet has to say. Especially at his age. If he feels he is strong emotionally and physically, and he has a good shot, go for it. You will know within a few days based on his reaction.

If the vet feels the cancer is too far gone, then make his last days the best he's ever had. After all your pet has done that everyday of his life with you.

My sympothies and thoughts. This is not an easy decision.