Osteosarcoma is the most common type of bone cancer in dogs. It’s an aggressive cancer that usually affects the legs of large and giant breed dogs. The first sign is often a limp that doesn’t go away. While osteosarcoma is serious, treatment can relieve pain and give many dogs good quality time with their families.
Osteosarcoma is a cancer of the cells that make bone. It destroys healthy bone and replaces it with weak, abnormal bone. This causes pain and can lead to fractures. Osteosarcoma also tends to spread, most often to the lungs. Many dogs already have tiny areas of spread that can’t be seen at the time of diagnosis.
Osteosarcoma is most common in large and giant breed dogs, including:
It usually affects middle-aged and older dogs, but it can occur in younger large dogs too.
Osteosarcoma most often develops in the long bones of the legs. Common sites include:
It can also affect the jaw, ribs, spine and skull.
A limp that lasts more than a week or two in a large-breed dog should always be checked. Our articles on my dog is limping but still playing and signs your dog is in pain explain what to watch for.
Your vet may:
Removing the affected leg removes the source of pain. Most dogs adapt very well to life on three legs, often within a few weeks.
Chemotherapy after amputation helps slow the spread of cancer. Dogs usually handle chemotherapy well, with fewer side effects than people.
The outlook depends on the dog and the treatment chosen. With amputation and chemotherapy, many dogs live around a year or longer, and some live much longer. Without treatment, the cancer progresses quickly and pain becomes hard to control. Your vet or a veterinary oncologist can explain what to expect.
Whatever you decide, keeping your dog comfortable is the priority. Our quality of life scale for dogs and cats can help you track how your dog is doing.
There’s no known way to prevent it. Early checks for limping help catch it sooner.
Yes. Most dogs adjust quickly and return to walking and playing.
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