Lump Under Dog's Skin That Moves. Most dog owners worry that a hard lump could be skin cancer. They remain relatively mobile (skin moves.
Lumps and bumps on a dog's skin can have many underlying causes, which owners often divide into two categories: As your pet becomes older, you are more likely to find a lump under the dog’s skin that moves. If a bump is in the skin, it will move with the skin rather than just sit there as the skin moves.