No pet parent wants to imagine the big C happening to their dog. Cancer is scary no matter the type, but bone cancer is extremely painful and serious. There's no such thing as a "good" type of cancer, but osteosarcoma is definitely one of the more aggressive ones.
Osteosarcoma in dogs is not very common, but when it does strike, it requires swift veterinary attention. Here's what pet parents need to know.
Osteosarcoma is a malignant and aggressive tumor that affects the skeletal system of dogs, humans, and other animals. It often develops in the long bones of the limbs—especially the humerus, radius, femur, and tibia—but it can affect any bone in the body, including the jaw, skull, spine, pelvis, or ribcage. Osteosarcoma can grow rapidly, causing destruction of the bone that leads to severe pain, instability, and fractures.
Could Your Dog Have Cancer? Keep an Eye Out for These Warning Signs What Causes Osteosarcoma?
Scientists are not sure exactly why osteosarcoma develops (or many other types of cancer, for that matter), but there does appear to be a genetic component. While this type of cancer can affect dogs of all breeds, it's most common in large and giant dog breeds, including:
Osteosarcoma occurs most often in middle-aged and senior dogs, but even young dogs can be affected.
What Are the Signs of Osteosarcoma in Dogs?
Bone cancer hurts! The first sign of osteosarcoma in dogs is often sudden pain in the affected area. If in a limb, the dog will likely begin limping and may hold up the painful leg. This limping may come and go at first, leading pet parents to believe it's just a minor issue like a sprain or strain. However, the limping will not go away with rest and medications, as it would with a minor injury.
As the tumor grows, you may notice swelling in the affected area. Over time, the pain becomes worse and the bone may actually break. Because of the bone destruction caused by cancer cells, these fractures will not heal with treatment.
How Fast Does Osteosarcoma Spread?
Osteosarcoma in dogs tends to metastasize quickly to other parts of the body, especially the lungs. The rate of this spread can vary from case to case, but many dogs already have metastasis by the time they show signs of pain. Early detection and treatment of osteosarcoma can prevent or slow the spread of this cancer.
Your veterinarian will do diagnostic tests to determine if the cancer has spread and how much. This is called staging and usually involves lab work, X-rays, and ultrasounds. Some dogs will need advanced diagnostic tests like CT or MRI. Your primary vet may refer you to a veterinary oncologist for staging and treatment.
How Is Osteosarcoma in Dogs Treated?
Because of the aggressive nature of this cancer and the severe pain it causes, treatment should be started ASAP. Specific treatment is dependent on the location of the tumor, but the primary goals of treatment are to alleviate pain and prevent or slow metastasis. Most dogs are treated with pain medications such as carprofen and gabapentin. Your veterinarian will discuss the best treatment options for your individual dog.
Surgery
In most cases, the recommendation is to remove the primary tumor, if possible. This often involves amputation if the tumor is in a limb.
Most dogs adapt well to life as a tripod! Three healthy limbs are more than enough for dogs to run, jump, play, and enjoy life. Amputation removes the source of pain (recovery pain from surgery is much milder) and improves overall quality of life. Surgery may even cure the cancer or lead to remission if the cancer has not spread.
