Cancer risks in cats and dogs

Cancer Risks in Cats and Dogs By Theresa A. Fuess, Ph.D. Information Specialist University of Illinois College of Veterinary Medicine
“Spaying and neutering can reduce the risk of cancer. Dogs spayed before the first heat cycle have only half the risk of mammary carcinoma of those spayed after the first but before the second heat cycle. Dogs spayed after the fifth heat cycle or never spayed have the highest risk of mammary cancer. Testicular carcinomas or tumors in dogs are common, but having your dog neutered eliminates that risk. Fortunately, testicular cancer rarely spreads in dogs, unlike in human beings, so treatment has a high success rate.”<