Mast cell tumors are more common then you think. They can be any where on the body from foot pads to the tips of the ears. These types of tumors are most common in boxers but will appear in all other breeds as well. These tumors can be big or they can be small little circular red or black marks. I've seen them on many parts of the body. Ones of the pad paws are not as rare as you think. Elaine, I remember reading about poor newman when you were going through that troubled time with him. The next day at work i asked the surgeon if he'd seen MCT on the pads before and he said yes. He's been doing this for over 30 years as well, but in the surgical field, not general practice. i asked what could be done about it and he said either toe amputation if it was just on a digit or leg amputation if it was more spread out. I'm sorry the results of the CT scan showed that it had spread. MCT are a horrible cancer because it spreads like wildfire. When you hear those three letter a sense of dread overcomes you because you know even if they are removed and chemo is started you don't have much time left with you pet.