You might want to check on http://www.shirley-wellness-cafe.com There is lot of information for animals. I thought I saw something mentioned under oxygen therapy.
Our 15 year old cat had it in the jaw. At that time I only read regular vetenarian stuff. And we decided to keep him comfortable. They had surgery for it but everyone said after awhile the jaw would start hanging and the cat would not be able to eat. Since we know how stressful it is for animals to go to a vet, we decided we should not be selfish and think of him first. Eventually had him euthanized, we shed a lot of tears but we knew we did the right thing for him.
There 2 people on the forums with dogs and cancer and they were trying different alternatives too. I can't remember the forums, I hope they read your message.
There is a search box on the website, type in cat with cancer.