Bone Cancer in Dogs

Canine osteosarcoma or bone cancer in dogs is a very aggressive tumor which affects the bones of the dog, causing severe pain and is also malignant. Every year, approximately 10,000 dogs are said to be diagnosed with bone cancer. There are two basic groups of cancer in dogs; primary bone cancer that originate from the bone and metastatic bone cancer that migrate to the bone from another part of the body that is affected by cancer. This disease can develop at any age, but they are most likely to occur when the dog is old. Bone cancer mostly affects breeds whose body structure is big.

Types of Canine Bone Cancer

• Fibrosarcoma, is a locally aggressive tumor that has a low tendency to spread unless the tumor is malignant.
• Osteosarcoma is a highly malignant tumor that affects dogs and is diagnosed after it has metastasized for about 95% of the dog.
• Chondrosarcoma is less aggressive than fibrosarcoma, but spreads on a wider area than osteosarcoma.
• Synovial cell carcinoma is another type of bone cancer that causes complete bone destruction. Grade 1 and Grade 2 synovial cell carcinoma is potentially curable but, Grade 3 usually results in death.

Symptoms of Bone Cancer in Dogs

Osteosarcoma can be easily detected in dogs by observing signs like:

• Limping and becoming lame, that affects the leg where the cancerous tumor is present. The lameness may not be so evident in the beginning, but as the size of the tumor increases, it causes more damage to the bone tissue making it more painful leading to permanent disability of the dog.
• A hard swelling will be observed on the affected part of the dog that may increase in size as the days go. The dog's behavior tends to change due to extreme pain in the affected part.
• A condition called pathological fracture, where the bones become weak and tend to break easily even due to minor injury will also be observed.

Causes of Bone Cancer in Dogs

Though the cause of osteosarcoma is not exactly known, it has been noted that tumors generally develop in the growth plates. It has also been observed that male dogs are affected more than their female counterparts. A diet that can stimulate rapid growth and development is thought to play a significant role in the development of malignant tumors. Other factors that can cause osteosarcoma in dogs include, bone infections as well as bone fractures, exposure to chemical carcinogens and ionizing radiation, etc. Castrated males and spayed females are also at a risk of contracting bone cancer.

Treating Osteosarcoma in Dogs

This illness can be treated using the following methods:

• An X-ray or radiography is carried out in order to reveal any development of tumor or any characteristic bone patterns like lytic lesion.
• If the X-ray does not reveal a clear picture, then the doctor may suggest a biopsy, which can confirm the presence of cancerous tumors.
• Another common treatment is amputation of the affected limb. Limb sparing is also carried out if the cancer has not affected a major part of the bone.
• Chemotherapy coupled with surgery is a primary form of treatment carried out in order to avoid amputation and it also prolongs the life of the canine.
• Chemotherapy drugs like cisplatin, carboplatin and doxorubicin are used to alter the course of osteosarcoma.
• Non steroidal anti-inflammatory medications and analgesics like aspirin, butorphanol, carprofen and tramadol are used to provide temporary relief from pain and discomfort.

In case you identify any symptoms related to bone cancer, in your pet dog, consult a veterinarian immediately for timely detection and treatment of bone cancer.