Cancer and tumours

Our dogs are susceptible to the same types of cancers as we are, and they can affect any and every organ in the body. While some tumours on the skin are obvious and lumpy, some cancers can be hard to identify, but it’s important to remember that not all tumours are cancerous and not all cancers are malignant (aggressive).

The most common cancer and tumour related claims we see are:

  • Mast Cell Tumour
  • Lymphoma
  • Lipoma
  • Sarcoma
  • Abdominal Tumour
  • Carcinoma
  • Adenoma
  • Histiocytoma
  • Osteosarcoma
  • Melanoma
  • Adenocarcinoma


There are several signs that can help you determine if your dog has cancer, but these often vary depending on the system or part of the body it is attacking, and other factors. These can include:

  • Loss of appetite
  • Weight loss
  • Vomiting and diarrhoea
  • Lumps and bumps
  • Any kind of swelling
  • Lameness
  • Difficulty in breathing
  • Lethargy and weakness

These can be signs of other conditions in your dog and some are easy to spot while others are not, so it’s important to speak to a vet as soon as you notice any unusual behaviours or signs of illness.


Some breeds might be more at risk from certain types of cancer but otherwise, the cause of tumours and cancers is wildly unknown. We know that cancer is the uncontrolled growth of cells and these are either benign (slow-growing, removable) or malignant (fast-spreading, aggressive).

Prevention and treatment

Because the causes of the different types of cancers are largely unknown, prevention is extremely difficult. Being able to recognise the symptoms can help with early detection, which can help greatly.

Once the necessary tests have been completed to confirm the existence of a tumour, whether it has spread to other parts of the body, and to see if it is cancerous, a vet will suggest their recommended treatment.

This can depend on the kind of lump, its location and severity, but the basic type of treatment usually includes surgery, chemotherapy or radiotherapy.

If the tumour or cancer is having a severe effect on the dog’s quality of life, euthanasia might be recommended.

If you notice any changes in your dog’s behaviour, or you think they have a tumour or cancer, visit your vet.

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