November is National Pet Cancer Awareness Month, so there’s no better time to talk to your clients about the different types of cancer and the symptoms to watch out for.—a site committed to canine cancer awareness—reports that one in three Aussie dogs will be affected by cancer in their lifetime. This is a scary statistic that pet parents should be privy to. Indeed, it’s also essential for pet owners to understand the different types of cancer and the symptoms. The following information may be useful to help raise awareness of pet cancer amongst pet owners.

Common types of pet cancer

Just like in humans, cancer can affect practically any part of the body. It is common in both cats and dogs. The most common cancers are detailed below.


While Lymphoma can affect any breed of dog, it is more common in certain breeds. Boxers, Border Collies, Cocker Spaniels and Golden Retrievers, for example, are more prone to developing this particular type of cancer.

The disease presents as a lump or bump. It can grow anywhere on the body but is more obvious in certain locations, such as at the back of the rear legs, where the dog’s jaw meets the neck and in front of the shoulder. This is because the lymph glands in these particular locations are closer to the surface of the skin.

Mast cell tumours

Mast cells release active chemicals that are necessary for the body to function. However, becoming cancerous can cause the cells to over-produce chemicals, which can damage the body.

Mast cell tumours can be found throughout the body. Yet, the most commonplace to find them is on the skin, in the spleen, liver and bone marrow. A biopsy is needed to diagnose mast cell tumours and, depending on the grade of tumour, survival rates can be positive.


Melanomas are most frequently found on the skin, the mouth and the nail bed. It typically presents as a dark brown spot with associated swelling. Surgery can be a successful treatment, providing the tumours have not spread throughout the body.


Osteosarcoma is a common bone tumour found in dogs. It most commonly affects the limbs. Dog breeds more at risk of developing Osteosarcoma include Mastiffs, Rottweilers, Greyhounds and Great Danes. Given that Osteosarcoma can be painful, pet owners can look out for signs of tenderness or soreness, as well as behavioural changes that may be associated with pain.


Haemangiosarcoma affects blood vessels. Dermal haemangiosarcoma impacts the skin, while hypodermal or sub-cutaneous haemangiosarcoma is found in the spleen or heart. However, despite the three variants, it is in the spleen that this type of cancer is most commonly diagnosed.

It tends to affect middle-aged to older dogs and is displayed as a red or black growth on the hairless areas of a dog’s skin. Hypodermal or sub-cutaneous tumours are not visible. Nonetheless, they may be identified via the outward symptoms such as lethargy, swelling of the abdomen, weight loss, lack of appetite and coughing.

Recognising the symptoms

The American Veterinary Medical Association (AVMA) states that approximately 50% of dogs over the age of 10 will develop cancer. By increasing pet owners’ understanding of cancer and awareness of the signs and symptoms, early action can be taken.

Possible signs of cancer in pets include (source: AVMA):

  • Abdominal swelling
  • Bleeding from the mouth, nose or other body openings
  • Difficulty breathing
  • Difficulty eating
  • Lumps, bumps or discolored skin
  • Non-healing wounds
  • Persistent diarrhea or vomiting
  • Sudden changes in weight
  • Unexplained swelling, heat, pain or lameness
  • Visible mass/tumor

Preventative measures and early detection

While a pet cancer diagnosis can be incredibly scary for pet owners, it’s important to point out that early detection is key to successful treatment.

Regular checks and early action is the best way to prevent and manage cancer in pets. The Pet Industry Association of Australia (PIAA) recommends pet owners take the following preventative measures:

  • Schedule regular pet health checks
  • Frequently examine pets’ bodies for any lumps, bumps or abnormalities
  • Assist pets to maintain a healthy weight
  • Take action to protect pets from sunburn to help prevent melanoma
  • Reduce environmental risks, such as passive smoke, harsh chemicals and pesticides

Pet professionals play an important role in reminding owners of the simple steps they can take to help prevent their pets from developing cancer, or at the very least reduce their risk.

Information sources:

  • Cancer in Pets. AMVA. Accessed online Nov 2020 via
  • PIAA.
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Liz has a passion for all things cat and dog, and was one of the first in Australia to bring Pet Insurance to the market. She has headed up Petsecure for the past 12 years, and is committed to promoting and supporting the amazing work done by rescue groups around Australia, and those who work to promote a better life for all animals.

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