Is this a tick, a tumor? Outdoor kitty. I only.moved here a yr ago but I look after him. Already fixed but hes definitely an outdoor cat. I was able to squeeze some revolution on his neck but didn't get the whole tube on him before he ran away. I do have a preserve near me. Deer, etc so it.could be a tick but I've never seen them this big. Pretty gross. From what I can tell it did appear suddenly.