I don't believe there's any known human ones, but there's a dog one that is 11,000 years old (Canine Transmissible Veneral Tumour) and there's a clam one.
The dog one is rampant where I live in Mexico. Treatable of catched early and the dog is lucky enough to have someone affluent watching over it, but most don't.
What name(s) do you have for it? What's the philology?