I'm so so very sorry to hear of your loss of Bobby.
I have a gorgeous persian cat called Honeybear, who we nickname him Shag Nasty as he loves to shag jumpers and dressing gowns etc.
I had to take him to the vets a coupla weeks ago because he suddenly started to lose weight and when the vet felt underneath him I had to look away as I wonder about tumours etc. When I looked back at the vet she said to me that he has very enlarged kidneys and she isn't even sure if he has tumours on them and whether or not the tumours could be cancerous. I really surprised myself by not crying there and then but my Dad was with me to support me. As he is coming up to 15 in June she said it wouldn't be worth doing blood tests or a biopsy as there is nothing they can do anyway. He is now on meds (a pill a day) for life. On top of that he also has a heart murmur. I just gotta give him all the love I can and look after him which I have done since he was born. I love him to bits and dread the day we will have to make that awful decision.
Here are a coupla pics of my baby...