Can cats get cancer? Dogs, cats, and other animals can get cancer just like we humans. Around one third of cats in the USA over the age of ten will be diagnosed with some form of cancer. Cats are experts at hiding illness and can be sick for a very long time before their humans realize something is wrong, so be alert for warning signs and take your cat to the vet for regular check-ups. Going outside the box is a common warning sign for many types of illness, and can indicate everything from stress to urinary issues. Other things to look for include: Loss of appetite Unexpected weight loss Difficulty eating Bleeding from the mouth or nose Lumps or bumps that increase in size Sores that don’t heal Lack of energy Difficulty breathing The sooner a health issue is discovered, the better the chance of treating it. Your cat may meow they don’t want to go see the vet, we don’t always want to go see a doctor either, but it’s better to get an issue looked into.