After a round of antibiotics that didn't help I'm taking my dog back to the vet today. Her paw is still swollen and I've been reading about mast cell tumors and such. Because this has to do with histamine and mast cells I have to ask this. My dog is always scratching here and there. I was thinking it was the fleas and that they bother her more than the other dogs. But after reading about histamine and mast cells I'm wondering if could this scratching be a sign of skin disease? Of course I'm going to ask the vet today. But I really want a practical answer. If it is cancer I will be putting her down. I had a dog as a kid with a bad skin condition. Watched him constantly go to the vet for treatment only to have to have him put down. I don't want my dog to be miserable like my Max was.