Osteosarcoma is the most common type common type of primary bone cancer in dogs accounting for up to 85% of tumours that originate in the skeletal system. Osteosarcomas are seen most often in the long bones of the limbs, most often ‘ near the knee’ ‘away from the elbow’, but can also affect any bones in the ‘axial’ skeleton (head, spine, ribs). Large & giant breeds are at higher risk for bone cancer, especially in the long bones.
Factors that affect growth rate such as diets that promote rapid growth in puppies appear to influence risk. There is ongoing research that also suggests a link between early neutering (under 12 months of age) and bone cancer. (Enogenous Gonadal Hormone Exposure and Bone Sarcoma Risk)
The disease usually shows itself during middle age (7 – 10 years) and it is safe to assume that the disease, by the this time, will have already spread to other areas.
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