Pets Get Breast Cancer, Too

many people don't realize that pets can also suffer from breast cancer. mammary gland tumors are common in dogs and cats that aren't spayed or were spayed late.

cats generally have eight mammary glands (four pairs). dogs vary, but usually have 10 glands. around 90 percent of feline mammary tumors are malignant; in dogs, less than 50 percent are malignant.

to prevent mammary gland cancer, spay your pet before she goes into heat. dogs spayed before their first heat are 2,000 times less likely to develop breast cancer. cats spayed before their first heat have 91 percent less chance of developing breast cancer. after just one heat, the risk rises. around four months of age is a good time to have your pet spayed, as vaccinations are generally completed by then.

just like in people, mammary exams for pets are important. early detection is key. for example, cats with mammary tumors removed when less than 2-centimeters in size have a median survival time of four-and-a-half years, while cats with tumors that are bigger than 3-centimeters have a median survival time of six months.

once your dog or cat is five years old, perform a mammary exam monthly. gently feel the tissue under and around each nipple, "rolling" the tissue between your fingers. if you feel even a tiny lump, bring your pet to the veterinarian.

the primary treatment is surgical removal. depending on the situation, your pet may have only the affected gland removed, several glands in the area or all glands on that side. the tumor will be analyzed to determine if it's benign or malignant. if malignant, your veterinarian will likely refer you to a veterinary oncologist for advice.

-- louise murray, dvm, dacvim, is director of medicine at aspca's bergh memorial animal hospital, and author of vet confidential.