If your large breed dog suffers from lameness that doesn’t respond to treatment, insist on x-rays.
Please remember that many dogs don’t get diagnosed until the bone had eroded to the point when it broke. It is always better to be safe than sorry.
What is osteosarcoma?
Osteosarcoma is the most common bone cancer in dogs—about 85% of all cancers affecting the bone. Osteosarcomas are malignant, aggressive, and extremely painful. Unfortunately, symptoms can be quite ambiguous—after all, limping can have all sorts of causes. Depending on the location, you might find firm swelling or a bump, but that might not be easily detectable everywhere. Further, things get even more clouded when osteosarcoma affects other bones than in the legs.
Other potential, non-specific symptoms include:
- loss of appetite
- weight loss
- reluctance to exercise
Further information: Bone Tumors in Dogs
Common osteosarcoma sites
Osteosarcoma affects mostly large breed dogs and it is most likely to develop at the ends of long bones such as:
- radius at the wrist
- humerus at the shoulder
- femur and tibia around the knee
Wallace was a middle-aged Standard Poodle. He was a happy, active, well-loved boy. He had a wonderful mom and a fantastic life.
One day, after his playtime, Wallace returned to the house favoring his leg. He always played with great vigor, and it was reasonable to assume he might have sprained something. When the veterinarian examined Wallace, he agreed that Wallace sprained or strained something.
Wallace was limping only slightly, bearing weight on the leg and didn’t seem overly upset about it.
The limp doesn’t go away
As the time went on, the injury didn’t seem to want to heal. Wallace would get better and then start limping again. Shouldn’t a simple sprain have resolved by now? It always looked like it did and it always came back.
Then, when his mom was grooming Wallace, she found a swelling above his right wrist. It didn’t seem to hurt and it was hard to see in all his fur. What is it? She decided to shave the fur off to get a better look. With the fur gone, it was apparent that there was quite a large growth.
What is that bump?
Given her experiences, the first thing that came to Wallace’s mom’s mind for cancer. Her heart sank, and she was trying to come up with another idea of what it could be. Perhaps it’s just some sort of infection? Maybe swelling from the soft tissue injury? Wallace didn’t seem to be bothered by it.
She made an appointment with the veterinarian, which was to include x-rays.
Wallace limped into the clinic but looked his normal happy self. The staff all knew him and it was a cheerful greeting. Wallace didn’t look or act as if there was something seriously wrong.
However, when the veterinarian examined Wallace’s leg, her expression changed from cheerful to serious. She was suspecting the same thing Wallace’s mom did—bone cancer. However, Wallace had no pain response to any pushing, pulling or pressing of his leg. Bone cancer is crazy painful—perhaps it really is an infection or abscess.
Unfortunately, x-ray imaging shattered all hopes. Wallace indeed had osteosarcoma.
Wallace’s Story: A Journey Through an Osteosarcoma Diagnosis
Bone Cancer in Dogs: What You Need to Know