When our older cat was deemed "too old" to be treated by most of the other vets in town the Feline Medical Center was the only place that took us seriously about finding her life to be valuable even though she was old. Had we found them sooner I can't say we'd have prolonged her life, but I do think her life would have been healthier during her last years.
We started looking for a good vet when our cat showed signs of having skin cancer at 15, this was considered too old to treat by her regular vet and by a half dozen other vets (although they were all happy to take a fee to tell us that). We found the Feline Medical Center when she was 17, and they took us seriously and put her on some medications to slow the growth of the tumor. Had we found them earlier her cancer might not have spread so obviously. It made our vain little cat very upset to have this blemish on her coat --
She lived to be 18, 3 years with the cancer that no other vets thought she'd live long enough to treat seriously.
I can't recommend these vets highly enough. They love cats and will take your concerns to heart.