Chondrosarcoma of the Bone in Cats
Chondrosarcoma (CSA) is a type of cancer that affects the cartilage of the body; the connective tissue that is found between the bones and joints. Chondrosarcoma of the bone is a fast spreading form of bone cancer, which can be life threatening if not diagnosed and treated early. Chondrosarcoma arises from cartilage, metastasizing to other parts of the body, including the ribs of the affected cat.
The majority of CSAs involve flat bones, with about 30 percent occurring in the nasal cavity and about 20 percent involving the ribs. This form of cancer also affects the limbs, with a resulting weakening in the structure of the bone due to the invasive tumor. Fractures of the bone are common. Fortunately, this type of tumor is relatively uncommon in cats.
Symptoms and Types
- Lameness if tumor is affecting the leg
- Pain in affected area; e.g., limb
- Swelling at tumor site
- Sneezing and difficult breathing if tumor involves the nasal cavity
- Nasal discharge and/or nose bleed if tumor involves the nasal cavity
- Fracture in the bone of the affected limb
- Other symptoms will depend upon the metastatic site(s)
Although an exact cause has not been identified, multiple cartilaginous growths or protuberance may lead to this form of cancer.
You will need to give a thorough history of your cat’s health and onset of symptoms. Your veterinarian will perform a thorough physical exam on your cat, including a complete blood count, a biochemistry profile, and a urinalysis. The results of these tests are usually within normal ranges. Tissue samples from the local lymph nodes will also be taken for analysis of cancer cells and evidence of immune system response.
Radiographic studies of the affected areas may show the extent of the invasion. X-rays, computed tomography (CT) scans, nuclear bone scans, and radiographic scans will usually be helpful in diagnosing the stage and type of the tumor. Bone scans may show involvement of soft tissue and adjacent bones. The most conclusive and direct method for making a diagnosis is normally by taking a biopsy of the growth for microscopic laboratory analysis.