Chondrosarcoma of the Bone in Dogs
Chondrosarcoma (CSA) is an aggressive and malignant type of cancer originating from the cartilage of the body, the connective tissue located between bones and joints. Without prompt diagnosis and treatment, Chondrosarcoma can pose a significant threat to life. It has a propensity to metastasize, often spreading to various parts of the body, including the ribs. Among dogs, it stands as the most prevalent rib tumor and the second most common primary tumor, comprising 5 to 10 percent of all primary bone tumors.
Typically, Chondrosarcoma affects flat bones, with approximately 30 percent of cases occurring in the nasal cavity and roughly 20 percent involving the ribs. Additionally, it impacts the limbs, causing structural weakening of the bone due to invasive tumor growth, which frequently leads to fractures.
Large dog breeds and older dogs are at a heightened risk of developing Chondrosarcoma. While the cancer predominantly afflicts dogs around eight years of age, it can manifest in canines of nearly any age.
Symptoms and Types
- Lameness will be evident if the tumor affects the leg.
- Pain will be experienced in the affected area, such as the limb.
- Swelling will occur at the site of the tumor.
- Sneezing and breathing difficulties may arise if the tumor involves the nasal cavity.
- Nasal discharge and/or nosebleeds may occur if the tumor involves the nasal cavity.
- Fractures may develop in the bone of the affected limb.
- Additional signs will vary depending on the site(s) of metastasis.
Causes
While an exact cause remains unidentified, the presence of multiple cartilaginous growths or protuberances may contribute to the development of this type of cancer.
Diagnosis
To diagnose your dog’s condition, provide a detailed history of its health and symptom onset to your veterinarian. A comprehensive physical examination will be conducted, along with tests including a complete blood count (CBC), a biochemistry profile, and a urinalysis. Typically, results from these tests fall within normal ranges. Tissue samples from local lymph nodes will be extracted for analysis of cancer cells and signs of immune system response.
Radiographic assessments of the affected regions can reveal the tumor’s extent of invasion. X-rays, computed tomography (CT) scans, nuclear bone scans, and radiographic scans are usually instrumental in determining the tumor’s stage and type. Bone scans may indicate involvement of soft tissue and neighboring bones. The most definitive and direct diagnostic method typically involves obtaining a biopsy of the growth for microscopic laboratory analysis.
Treatment
Given the highly aggressive and life-threatening nature of this tumor, prompt treatment is essential. In cases where there is no metastasis (spreading) of the tumor in the affected limb, amputation or limb salvage is typically recommended. For nasal tumors, radiation therapy is usually the preferred treatment option. Additionally, radiotherapy may aid in prolonging the lifespans of dogs with inoperable tumors.
If the tumor involves the ribs, your veterinarian may opt to remove the affected ribs and nearby lung tissues through a wide excision to prevent metastasis. Chemotherapy may also be suggested, although its effectiveness in treating CSA has not been fully evaluated. Presently, surgery remains the primary treatment for this disease.
Living and Management
Your veterinarian may recommend follow-up evaluations every three months to monitor your dog’s condition. During these visits, your veterinarian will assess for any signs of metastasis. Routine X-rays of the affected area and other body regions will be taken to check for tumor recurrence and spread.
After surgery, expect your dog to experience some soreness. It’s important to limit your dog’s activity until it has healed, providing a quiet resting place away from high-traffic areas, other pets, and active children. If controlling your dog’s movement proves challenging, cage rest may be considered, with food dishes placed nearby for comfort. Gentle walks close to home are advisable, but if your dog experiences too much discomfort to go outside, indoor arrangements for relieving itself should be made temporarily. Seek advice from your veterinarian on the best approach for your dog.
Following leg amputation, most dogs adapt well and lead happy, comfortable lives.
Effective pain management is essential for treating chondrosarcoma; your veterinarian will prescribe appropriate painkillers. Adhere strictly to medication instructions, as overmedication is a preventable cause of pet fatalities.
Nutrition plays a crucial role in swift recovery. Monitor your dog’s food and water intake, ensuring it remains adequately hydrated and receives sufficient nourishment without overfeeding. If your dog is unable to eat on its own, your veterinarian will provide guidance on using a feeding tube for stomach administration of food.