Bone tumors in dogs are not uncommon, with osteosarcoma being by far the most common type.
Bone tumors are most common in large and giant breed male dogs, and are usually seen 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 primary tumor site, and they are common as well.
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.
Diagnostic procedures include x-rays, examination of a small sample of cells from the area under a microscope, and taking a biopsy.
A biopsy can be very valuable in determining the degree of malignancy of the tumor and predicting how it may behave in the body, which are both important in determining a prognosis. Your veterinarian may refer you to a specialist or veterinary teaching hospital for more specialized tests or treatment.
Surgery is the most common treatment of bone tumors in dogs.
If the tumor is benign, simply removing the lump is usually all that is needed.
If the tumor is malignant, more extensive surgery is usually needed, often including amputation of the leg. Unfortunately, in most dogs with a malignant bone tumor, the prognosis is usually poor because metastatic cancer develops even after the primary tumor has been removed. Radiation and chemotherapy can be used in some cases to prolong survival time but cannot cure the disease. Pain control is extremely important to keep your pet as comfortable as possible.