A Primer On Bone Tumors In Dogs
Bone tumors in dogs are not uncommon. However, osteosarcoma is by far the most common type.
Bone tumors are most common in large and giant breed male dogs and usually appear on the front legs. Unfortunately, most bone tumors are malignant and spread, or metastasize, to other areas of the body, often the lungs.
Metastatic bone cancers are ones that have spread to the bone from another tumor site. Unfortunately, they are common as well.

What does it look like
Signs of a bone tumor usually include a hard swelling on the leg, lameness, and pain.
The leg may become more painful and feel hot as the disease progresses. Sometimes, a bone tumor will cause the leg to fracture.
Diagnosing bone tumors in dogs
Diagnostic procedures include:
- x-rays
- the examination of a small sample of cells from the area under a microscope
- biopsy.
A biopsy can be very valuable in determining the degree of malignancy of the tumor. That helps predict how it may behave in the body, which is both important in determining a prognosis. In addition, your veterinarian may refer you to a specialist or veterinary teaching hospital for more specialized tests or treatment.
Treatment of bone tumors in dogs
Surgery is the most common treatment of bone tumors in dogs.
Removing the lump is usually curative if the tumor is benign.
If the tumor is malignant, more extensive surgery is usually necessary. Unfortunately, that often involves the amputation of the leg.
Unfortunately, the prognosis is typically poor in most dogs with a malignant bone tumor. That is because metastatic cancer develops even after the removal of the primary tumor. Radiation and chemotherapy can be useful in some cases to prolong survival time but cannot cure the disease. Pain control is critical to keeping your dog as comfortable as possible.
Immunotherapy trials for the treatment of osteosarcoma in dogs
Immunotherapy involves finding ways to help the dog’s immune system recognize and fight bone cancer.
ELIAS Animal Health recently conducted a clinical trial to evaluate its ELIAS cancer immunotherapy (ECI®)—a vaccine-enhanced adoptive cell therapy—combined with surgery to treat canine osteosarcoma. The study enrolled 102 dogs at 10 study sites across the country.
The trial has concluded, and the results should be coming soon.
Further reading: Canine Osteosarcoma Clinical Trial
Jelly Bean’s story: Clinical Trial Tests New Combinations of Immunotherapy Drugs to Treat Osteosarcoma
Related articles:
Common Limping Misdiagnoses in Dogs
Further reading:
Bone Cancer in Dogs: What You Need to Know About Osteosarcoma
Amputation for Dogs with Osteosarcoma Cancer
Canine Osteosarcoma: Teaching an Old Dog New Tricks