My yellow lab was absolutely loaded with fatty tumors from the time he was about 9 years old. We only removed them when they got too big and interfered with his walking. All were benign except for one small one (looked different, it was very dark and it had no hair on it) but they were sucessful in removing the entire growth and a good deal of skin around it and he seemed to be fine afterwords. He lived to be 13 and ended up having some huge masses in his abdomin and chest cavity that we chose not to operate on.

The vet asperated his many fatty tumors on a regular basis and they were only filled with fat, except for the ugly looking one which we had removed as soon as we saw it. All I would worry about are tumors which looks different then the fatty tumors.