Osteosarcoma [photo credit]
Osteosarcoma is the medical term for the prognosis of bone cancer. In dogs, it is the most common type of bone tumor, making up 85% of skeletal tumors. According to the National Canine Cancer Foundation, up to 8,000 dogs or more are diagnosed with osteosarcoma each year, with the low estimate being 6,000 cases.
Bone cancer starts deep within the bone and works toward the outside, causing great pain for a dog. Usually, osteosarcoma shows signs on the exterior when a dog limps, has lameness present in the leg, and sometimes exhibits slight swelling on the area where the dog feels pain. This type of cancer primarily affects dogs who are middle-aged to elderly; however, dogs of all ages can get it.
Most of the time, osteosarcoma is found when a veterinarian observes lesions on the bone through x-rays. From there, if cancer is found, blood work is likely the next step, and a bone scan that determines whether or not the cancer has spread to other parts of the body. A bone biopsy will ultimately confirm if the problem is cancer, and the type.
Risk factors of osteosarcomas are still being studied between breeds, gender, and age. Some studies have suggested that diets that support fast growth in puppies attribute to whether or not a dog will get bone cancer later in life. Other studies suggest that males have a higher risk than females. According to the University of Georgia’s College of Veterinary Medicine,
Osteosarcoma is most common in giant and large breed dogs (90%) and is uncommon in small and medium breeds. Breeds especially predisposed to development of OSA include Saint Bernards, Rottweilers, Great Danes, Golden Retrievers, Irish setters, Doberman Pinschers, and Labrador retrievers.
When a dog gets osteosarcoma, there are several options for treatment. In many cases, amputation of the limb is successful, but it is not a guarantee for the end of cancer. Also, some dogs are not good candidates for amputation due to certain health conditions, like obesity. Amputation is not always an option, as it depends on where the cancer is located. Radiation and chemotherapy are other forms of treatment for canine cancer, but overall, the method of treatment is going to depend on severity, willingness to put the dog through cancer care, and availability of treatment options.
Kramer, Monique T., D.V.M., M.S., Kenneth S. Latimer, D.V.M., Ph.D., Pauline M. Rakich, D.V.M., Ph.D., Royce E. Roberts, D.V.M., M.S., Nicole C. Northrup, D.V.M., and Perry J. Bain, D.V.M., Ph.D. “Canine Osteosarcoma.” University of Georgia’s College of Veterinary Medicine. Veterinary Clinical Pathology Clerkship Program , 2003. Web. 21 Sept. 2011.
“Osteosarcoma.” The National Canine Cancer Foundation, 2006. Web. 21 Sept. 2011.