By Theresa Arteaga, DVM, DACVIM (Oncology
Cancer is the number one disease-related cause of death in dogs and cats. It accounts for nearly 50 percent of reported pet deaths each year. As in people, prevention and early detection is key. It is also important to remember that amazing advances have been made in detection and treatment of pet cancer, and a high quality of life can be provided for your pet.
The cause of cancers in pets is multifactorial. There are certain breeds that tend to get certain types of cancer more often than others. Now that the canine genome is mapped, it is known that cancer has been unknowingly bred into certain breeds. There is significant research being performed to find the mutations that cause these cancers and create affordable screening tests to breed these mutations out. However, as in people, cancer is a disease of mutations, and living long enough is typically the main reason for getting cancer. Over a period of time, a dog or cat lives long enough for mutations to increase to point of eventually manifesting in cancer. Cancer occurs when there is a DNA mutation causing some genes to be damaged, changed or defected. If these cells with damaged genes are not destroyed by the body’s immune system, they will grow uncontrollably.
Pet cancer prevention is very similar to that in people. Here are some key points:
• Start with good nutrition. Remember that each dog is an individual and that there is not a “perfect” diet for all dogs. Whether a dog needs a novel protein, low-fat, or high-protein diet, it is important to find a good one for your pet early on, and you may need to change it as your pet’s needs change.
• Exercise. Regular exercise is critical. 50 percent of dogs in the U.S. are obese, and this leads to a variety of health issues, as well as cancer. Exercise reduces stress, builds the immune system and strengthens the bond between you and your pet.
• Stress. Reduce stress as stress can lead to pro-inflammatory and immune issues (i.e., stress diarrhea, weight loss).
• Minimize exposure to pesticides/herbicides and secondhand smoke. Pesticides and herbicides are reported in bladder cancer in Westies, and secondhand smoke has been attributed to lymphoma and lung cancer in dogs.
• Spay/Neuter. This is controversial, and depending on your breed, speak to your veterinarian. Spaying before the first heat lowers the chance of mammary cancer to 0.8 percent in dogs; however, early spaying has been implicated in hemangiosarcoma in Golden Retrievers and bone cancer in Rottweilers.
• Know your breed! Certain breeds are predisposed to certain cancers, so your veterinary care may be different for different dogs. Scotties, Westies, Shelties, and Aussies are all predisposed to bladder cancer, so you may want to start ultrasounds or at least urinalysis. Bernese Mountain dogs and flat coats are predisposed to histiocytic sarcoma. This should be discussed with your veterinarian.
• Annual/biannual exams with your veterinarian. It is reported in the literature that owners go to the vet more when they have a younger dog than older dog. Consider that as humans get older, we increase early-detection tests (i.e., mammograms, colonoscopies), so it follows that an older dog should also go to the vet more rather than less.
• Routine dentals. This has been controversial because of the anesthesia required. However, I can say that this is how most oral tumors are found. If an oral tumor is found because it got so big that the owner can see or smell it, then it is often not curable.
• Decrease inflammation. Chronic inflammation is a cause for 25 percent of human cancers. In dogs this can be chronic diarrhea, vomiting, dental disease, arthritis or skin disease.
• Finally, massage your pet frequently. If a lump or bump is felt, then a needle aspiration should be done and a map of your dog’s lumps/bumps kept, whether they are benign or malignant.
If your pet does have a diagnosis of cancer, again it is important to remember that there is often a treatment and this is not a death sentence. It is important to have a team approach, and your veterinarian will contact an oncologist who will advise you of the different options to best suit your pet. There are traditional modalities of surgery, radiation, and chemotherapy, but also immunotherapy and targeted therapies. It is also key to remember that you are an advocate for your pet, and whether you treat cancer or not, it is important to be educated to what is available and for your pet to be comfortable and secure through their journey.
Theresa Arteaga DVM, DACVIM (Oncology) acquired her veterinary degree at Cornell University Veterinary College. Her residency in oncology was at the Animal Medical Center in New York City, where she was on the team that brought DNA Melanoma Vaccine through USDA trial, as well as other targeted and immunotherapies. She remains active in lecturing, teaching, and clinical trials, and stresses the importance of multimodality treatment of cancer, as well as her patients having the best quality of life possible. Dr. Arteaga sees patients in Monterey and can be reached at http://animalcancercentermonterey.com.