What causes cancer?

In many ways, your dog is a lot like you. You both need the basics of proper nutrition and exercise to stay active and healthy. The bad news: Dogs can develop cancer, just like humans. The good news: Dogs have cancer treatments, just like humans.

Cancer generally arises from a single cell that has undergone a series of genetic mutations. Many environmental agents are capable of inducing changes in cells – viruses, chemicals, radiation, ionizing radiation and some hormones. The effects of many of these agents accumulate over a lifetime, possibly explaining why many cancers affect middle-aged and older dogs.

To help prevent cancer, be aware of your dog's risks so you can be proactive in keeping him healthy.

The risk factors for cancer in dogs include:

  • Age - Dogs are living longer, which increases the likelihood of cancer
  • Breed and Size - Certain kinds of cancer are more common in specific breeds such as German shepherd, Scottish terriers and golden retrievers. Some bone tumors are more common in dogs weighing more than 20 kg.
  • Gender - Some cancers are more common in one sex compared to another, such as mammary tumors in female dogs
  • Environment - Exposure to chemicals, such as pesticides or herbicides, may contribute to cancer

Does my dog have cancer?

  • Your veterinarian may need to perform several tests to establish a diagnosis, determine which organs are affected, and determine which therapy is best for your dog. The signs of cancer may include:
  • Abnormal swelling that grows or persists
  • Rapid or extreme weight loss
  • Ongoing and persistent sores
  • Significant change in appetite
  • Chronic bleeding or discharge from the mouth, nose, ears or anus
  • Offensive odor
  • Difficulty swallowing or eating

Other common symptoms include lack of interest in exercise, loss of stamina, persistent lameness or stiffness, breathing difficulties and difficulty going to the bathroom.

Treatment and the importance of nutrition

Early detection of cancer is the single most important factor for successful treatment. Many cancers may be managed with chemotherapy and this can reduce the severity of clinical signs and add quality to your dog’s life. Many dogs debilitated and who have undergone surgery benefit from dog foods with increased levels of protein and energy to help correct nutrient deficiencies and replenish body nutrient storage. The main goal of nutritional management for cancer is to markedly improve the success of cancer therapy and add to the survival time and quality of life for dogs with cancer.

The food your dog eats plays an important role in his overall health and well-being. Balanced nutrition is an essential part of an active, healthy lifestyle. When your dog has cancer, it’s even more important to feed the right dog food consistently. For accurate diagnosis and treatment options, always consult your veterinarian and ask them to recommend the best food for your dog’s cancer.

Questions to Ask Your Veterinarian about Cancer in Dogs

  1. What are the treatment options for my dog’s cancer?
    • Ask how nutrition works with other available options
  2. Should nutrition be a part of my dog’s treatment regimen? Would you recommend a Hill’s® Prescription Diet® dog food for my dog’s cancer?
    • What if I have multiple dogs? Can I feed them all the same dog food?
    • How can nutrition help? What is the benefit of feeding therapeutic nutrition as part of treatment which may include administering pills, shots or chemotherapy?
    • What are the pros and cons of using nutrition to help manage my dog’s cancer?
  3. How long will I need to feed the recommended dog food to my dog?
    • Ask how feeding a therapeutic dog food can help promote health for my dog with cancer
  4. What is the best way (email/phone) to reach you or your hospital if I have questions?
    • Ask if you need a follow-up appointment.
    • Ask if a reminder email or notice will be sent.
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