Understanding Bone Cancer In Cats

Bone cancer, also called fibrosarcoma, occurs when fibroblast cells begin dividing abnormally and form a mass or tumour, which can weaken the structure of the bone and damage the surrounding connective tissue. Bone cancer in cats does not always metastasise, but when it does, it typically spreads to the lymph nodes, skin and organs. The cause of bone cancer in cats has yet to be determined, but some researchers believe there to be a genetic predisposition in some cats. Here's an overview of the symptoms, diagnosis and treatment approach for bone cancer in cats.


Symptoms of bone cancer include swelling at the site of the tumour and localised pain, which may present as your cat being unwilling to be picked up or petted and withdrawing from social interaction. Depending on the site of the tumour, your cat may also experience loss of mobility, lethargy and bone fractures. Additionally, it's not uncommon for cats to lose their appetite when they are in pain, which can quickly lead to dehydration.

Diagnosis And Treatment Approach

Your vet will diagnose bone cancer by taking details of your cat's symptoms, conducting a thorough physical exam and collecting blood and urine samples, which will show if your cat's organs are functioning normally and if the inflammatory markers in their blood are elevated. Diagnostic imaging, such as an X-ray and CT scan, will be necessary to confirm the size of the tumour and whether cancerous cells have spread to other parts of the body.

The main treatment for bone cancer is surgical removal of the tumour and surrounding bone and connective tissue. When a limb is affected, it is sometimes necessary to amputate the limb, and your cat may need physiotherapy to help them adapt after an amputation. When cancerous cells have spread, chemotherapy or radiation therapy will be required in addition to surgery. In this situation, the prognosis is typically not good, so early diagnosis is key to your cat making a full recovery.

During treatment and recovery, your cat will need to have a quiet place to rest, and you may be asked to limit their physical activity for a period of time. This may mean you need to keep them indoors and separate from other pets or young children living in the house. Your vet will arrange regular post-treatment follow-up appointments with your cat to check that there is no further development of cancerous cells.

If your cat has any of the symptoms associated with bone cancer, schedule an appointment with your vet as soon as possible to prevent unnecessary suffering.