Pets with Mammary/Breast Cancer

 Breast cancer can unfortunately occur in any mammal and can be devastating when it affects our pets. Like any cancer, mammary tumors arise from the uncontrolled growth of abnormal mammary gland cells, and our pets are built with eight to twelve mammary glands, instead of just two like us. If left untreated, certain types can spread (called metastasis) to other mammary glands, lymph nodes, the lungs, and other organs throughout the body. In both dogs and cats, the majority of these tumors are identified as being malignant, at danger of metastasizing. Siamese cats also tend to be at higher risk.
While any pet can develop mammary tumors, these types of cancer are more likely to occur in older, female dogs and cats that have not been spayed. As with any cancer, prevention and early detection are very important for an ideal medical outcome. Cats and dogs that are spayed before they go into their first heat are less likely to have breast cancer and is why we recommend spaying puppies and kittens at five and a half to six months of age. Genetics also play a part in determining an animal’s risk.
We can’t determine if a mass is cancerous by just feeling it, but any mass should be brought to a veterinarian’s attention. Taking an aspirate or biopsy of the tissue is often the best way to find out more information. Mammary masses may affect just one or several mammary glands. The skin over the tumor may be ulcerated or infected and the nipples may be inflamed, with or without discharge.
Early detection and surgical removal of the masses is the best treatment option. Chest radiographs are important to check for metastases to the lungs. Following surgery, your veterinarian may recommend referral for radiation therapy or chemotherapy. These are designed to kill potential cancerous cells in either a focused area or throughout the rest of the body.
Please remember that any suspicious lump along the mammary glands should be examined by a veterinarian as soon as possible. If you have any further questions about your pet, please give us a call at Copper Hill Animal Clinic at 661-296-8848.