Dog Cancer 101

If you have a pet that has cancer, you are probably very very scared of what is going to happen to your pet. We are going to cover what cancer is, how common it is, types of cancer, symptoms, How is cancer diagnosed, myths and more I hope you enjoy read on to learn more (This has a bit about other pets please enjoy)

How Common Is Cancer?

Cancer in dogs has become quite common, with 50% of dogs that are over the age of 10 years will develop cancer at some point in their life. So don’t worry, you are not alone.

What Is Cancer

Cancer is a disease where cells grow uncontrollably, invading surrounding tissue and may or may not spread to other areas of the body. Like people, dogs can get various types of cancer, including Mast Cell Tumors, Melanoma, Bone Cancer and Hemangiosarcoma. This disease can be generalized (spread throughout the body) or localized (restricted to one area).

What Causes Cancer

Cancer is a “multifactorial” disease (meaning no known single cause. But vets do know that both hereditary and environmental factors can contribute to cancer in dogs.

Types Of Cancer

  • Lymphoma is a cancer of the lymph nodes it attacks the immune system
  • Hemangiosarcoma is a cancer of the blood vessels
  • Mast cell tumour is a type of cancer that can develop nearly everywhere on the body. However, it is often visible as a skin lesion.
  • Osteosarcoma (Malignant bone cancer) this is most common in larger breeds of dogs
  • Mammary gland carcinoma this is a cancer of the mammary glands and can often be prevented by spaying a female dog before the first time they are in heat


  • Lumps
  • Swelling
  • Persistent Sores
  • Irregular Discharge from any part of the body
  • Lethargy or Listlessness
  • Unexplained Weight Loss
  • Lameness
  • Black Tarry Stools (ulcers which can be caused by cell tumours)
  • Decreased or Loss of Appetite
    • Difficulty breathing, defecating or urinating 

How Does your Vet Diagnose Cancer?

If there is a lump, the first step is to do a needle biopsy, which removes a tiny amount of tissue for a microscopic examination of the cells. Surgery may be performed to remove the lump for the pathologist to diagnose it.

Xrays, ultrasound, blood evaluation tests may also be helpful to diagnose if it is a cancerous lump and if it has spread.

Which Dogs Are More Cancer Prone?

  • Cancer is more common in older dogs.
  • Boxers, Boston terriers and Golden Retrievers, Great Danes and Saint Bernards are more likely to get cancer.

How To Prevent Cancer?

  • Getting your dog spayed/neutered may reduce their chance of getting certain types of cancer.
  • Having your dog spayed before her first heat cycle will reduce her chance of Breast Cancer.


  • Conventional treatments include surgery, chemotherapy, radiation, immunotherapy or combinations of therapy.
  • Some cancers cant be cured you should remember that if your dog’s cancer isn’t curable there is still loads of things you can do to make your pooch feel better. Talk to your vet about the options. Remember, proper care and nutrition can make your dog’s life better.

When Should I Consult My Vet?

You should contact your vet straight away if your dog shows any signs of cancer. You may want to consult a vet oncologist, who are often employed by speciality veterinary practices.

How Much Does It Cost To Treat Your Dog?

The cost varies. There’s diagnostic testing which is needed before doing any kind of therapy, and it can cost from €200-€1000. Or there is cancer treatment this can be a simple surgery for €1000 – €15,000 if you’re dealing with something difficult that needs radiation therapy and chemotherapy for dogs with lymphoma. That can get very pricey.


Cancer treatment myths

  • Pets cant get cancer.

This is definitely not true. Sadly animal cancer is common, and around 50% of dogs over 10 years old will die from cancer, and 30% of cats will be affected by a tumour in their life.

  • There is more cancer now than before.

This is true and false. Cancer has increased in both humans and pets. Still, the number of cancer patients is likely to have grown because pets now live longer lives. Even though cancer can occur in younger pets, it is mostly seen in pets of an older age.

  • You shouldn’t treat your pet’s cancer because they will just die anyway.

While some tumours are aggressive and treatment may not help, but some other cancers can be cured. Most tumours are treated as chronic diseases. This means that a pet might eventually succumb to cancer. Still, treatment may give your pet a better quality of life for a lengthier period of time. 

  • It’s okay to watch and wait if your pet has cancer but not showing any signs.

For less aggressive tumours watching and waiting might be the right approach. For many tumours, this is the wrong way to proceed.

  • Your dog will go bald.

It all depends on the breed of your dog, and the type of treatment your dog is given. In the worst cases, it usually only causes a partial amount of hair loss if any. Hair loss can occur in non-shedding breeds, including the Bichon Frise, the Poodle and the Old English Sheepdog, Your dog will not be in pain if she loses her hair. And it will grow back after treatment.

I hope this helped you if your pet or your friend or families pet has cancer, please share, and I hope your pet gets the right treatment and lives a happy life

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