Not to be that guy, but animals of certain size are seemingly unaffected by cancer. I think Kurzkezadt (or however you spell it lol) did a video on why whales don't die from cancer.
It's been a while since I read about this, but as I recall, most animals (might just be mammals) won't die of cancer without genetic modification. They have immune system factors that humans are currently considered not to have. (Either that or we eat too much food for it to work, depending where the research is going these days, lol.)