Maggie - he did have a malignant melanoma on his foot.  Given the extensive surgery otherwise, they highly recommended amputation.  Otherwise, they would have had to remove the entire pad and then take pieces of the others to fill in what they removed due to the cancer.  At first that's where I was leaning, but after researching more and learning that it would create a lot of extra pain and longer recovery time, we did amputation.  It wasn't until a friend of mine asked me if I would rather have Smokey with three legs or not at all that put everything into perspective.  And I will forever be grateful to him!